Generally, all the skills from the SRD will work normally, see http://www.d20pfsrd.com/skills. I prefer to allow skills the broadest possible application. If you can give me a story about why a different skill might apply to a roll, I will permit use of a skill other than the primary one in question. If it's an acceptable story, the roll will be at -2. If it's a good story, you will roll at your regualr skill. If you knock my socks off, I'll give you a +2 or more. Some examples:
Survival may substitue for a Climb roll (I spent several months in a forest like this one as a teenager. I got familiar with how strong the branches are and what kind of spacing they grow in)
Sleight of hand may substitute for Escape Artist (On my way to the holding cell, I spot an old nail that may serve to pick the lock on my manacles and stuble so I can pick it up)
Knowledge: History can fill in for almost anything (Hey, I recall an old tale about how the Red Banner adventuring party once did blah blah blah, and the story goes that they ... found rubies just that size (appraise) ... told an outrageous lie about (bluff)... were able to block the oil nozzles with (disable device)... set his broken leg by (heal)... and so forth)
All characters will start off speaking Common and a regional language. Non-humans also get a Racial language. In addition, you can speak a number of additional languages equal to your bonus from INT. Common is considered the "Trade Language" in this portion of the world, and consists of loan words and special grammatical rules borrowed from many of the racial and regional languages. That's why anybody can take a guess at reading/ understanding tongues they do know really know with a Linguistics roll. Feel free to make up the names for your regional and racial tongues, and let me know so I can post them for the group to see.
New Skill -
Control Body. (CON, or WIS for Monks, Armor Check Penalty for shapechange use) A combination of the skill used by shapechangers in 3.5 and the old Autohypnosis skill. It is a class skill for monks and other ascetic-type classes, as well as shape changers. A shapechanger can use this skill to force their body to assume another shape. Lycanthropes must make a check at moonrise each night of the full moon to resist involuntarily assuming animal form. If you are injured, you must also check for an involuntary change after accumulating enough damage to reduce your hit points by one-quarter and again after each additional one-quarter lost. On a failed check, you must remain in animal form until the next dawn, when you automatically return to your base form. If you are aware of your condition, you may make one attempt to return to humanoid form (see below), but if you fail, you remain in animal form until the next dawn. if you are aware of your condition, you may attempt to use this skill voluntarily in order to change to animal form, assume hybrid form, or return to humanoid form, regardless of the state of the moon or whether you have been injured.
Skill Use DC Notes
Resist involuntary change 25 Includes overcoming magically-induced changes or polymorph magic
Return to humanoid form (full moon) 25 Or a return to a primary or natural form under difficult contions
Return to humanoid form (not full moon) 20 Includes returning to natural or primary form under normal circumstances
Assume hybrid form 15 Includes a partial change or changing to a form with combined aspects
Voluntary change to animal form (full moon) 15 Changing to a familiar secondary shape under conducive circumstances
Voluntary change to animal form (not full moon) 20 Assuming a familiar form in less-than-ideal situations
For game purposes, assume the full moon lasts three days every month.
Action: Voluntary changes are standard actions.
Try Again: You can check to resist an involuntary change once each time a triggering event occurs. You can retry voluntary changes to animal form or hybrid form as often as you like. However, on a failed check to return to humanoid form, you must remain in animal or hybrid form until the next dawn, when you automatically return to humanoid form.
Other Shapechangers also use the skill to assume different form. See the Notes column above under skill use. The skill also applies to spellcasters using shapechanging magic. DC's are a little higher than for natural shapechangers.
Skill Use DC Notes
Resist involuntary change 30 Some beings or powers can hijack control of polymorph magic
Return to natural form 15 Only applies to changing in combat or other duress, usually accomplished at will
Changes outside the usual scope of spell 20 Make a partial change affecting a larger or smaller part of the body than normal
Voluntary change of spell's effect 25 Altering spell effects to choose a different defined ability
Access form's exceptional ability 20 Allows use of an exceptional ability normally possessed by an assumed form
Access form's Supernatural ability 30 Allows use of a supernatural ability for the spell's duration
Access form's spell-like ability 35 Allows use of a single spell-like ability
Your mental training gives mastery over your body and the mind’s own deepest capabilities. You can attempt the following tasks:
Task DC
Ignore caltrop wound 18
Memorize 15
Resist dying 20
Resist fear Fear effect DC+2
Tolerate poison Poison’s DC+2
Willpower 20
Cancel Poison or disease Poison's DC +5
New Mental Save 25
Adrenal Surge 30
Ignore Caltrop Wound - If you are wounded by stepping on a caltrop, your speed is reduced to one-half normal. A successful check removes this movement penalty. The wound doesn’t go away—it is just ignored through self-persuasion.
Memorize - You can attempt to memorize a long string of numbers, a long passage of verse, or some other particularly difficult piece of information (but you can’t memorize magical writing or similarly exotic scripts). Each successful check allows you to memorize a single page of text (up to 800 words), numbers, diagrams, or sigils (even if you don’t recognize their meaning). If a document is longer than one page, you can make additional checks for each additional page. You always retain this information; however, you can accurately re-create it only with another successful check.
Resist Dying - You can attempt to subconsciously prevent yourself from dying. If you have negative hit points and are losing hit points, you can substitute a DC 20 check for your roll to see if you become stable. If the check is successful, you stop losing hit points (you do not gain any hit points, however, as a result of the check). You can substitute this check for the stabilizing roll in later rounds if you are initially unsuccessful.
Resist Fear - In response to any fear effect, you make a saving throw normally. If you fail the saving throw, you can make a check on your next round even while overcome by fear. If your control body check meets or beats the DC for the fear effect, you shrug off the fear. On a failed check, the fear affects you normally, and you gain no further attempts to shrug off that particular fear effect.
Tolerate Poison - You can choose to substitute a check for a saving throw against any standard poison’s damage or effect.
Willpower - If reduced to 0 hit points (disabled), you can make a check to take a normal action while at 0 hit points without taking 1 point of damage. You must make a check for each strenuous action you want to take. A failed check in this circumstance carries no direct penalty—you can choose not to take the strenuous action and thus avoid the hit point loss. If you do so anyway, you drop to -1 hit points, as normal when disabled.
Action: None. Making a check for these effects doesn’t require an action; it is either a free action (when attempted reactively) or part of another action (when attempted actively).
Cancel Poison or Disease - When poisoned or upon contracting a disease, the character can make a check on his or her next action. A successful check indicates the character does not have to make saving throws against the poison's follow-up damage, which he or she instead automatically ignores.
New Mental Save - If a failed saving throw indicates the character is affected by any mind-affecting powers, spells, or spell-like effects, a successful check allows an immediate second saving throw to resist the effect. If the mind-affecting effect normally does not allow a saving throw, a successful Autohypnosis check allows a saving throw.
Adrenal Surge - With a successful check, the character gains temporary hit points equal to 10 + his or her Wisdom modifier. The temporary hit points persist until lost. A character cannot check for temporary hit points more than once per day. Temporary hit points gained through Control Body do not stack with temporary hit points gained through any other source.
Trancing: The skill can be used to enter an altered state of consciousness or trance state, granting access to various abilities. To make a Control Body check for trancing, a character must be relaxed and motionless, as if sleeping.
Task DC
Sleep normally despite distractions 15
Sleep normally despite difficult distractions 20
Slow breathing down to half normal rate 20
Ignore pain or injury 20 + damage dealt
Body awareness 25
Heal at twice the normal rate 25
Slow breathing down to one-quarter normal 25
Feign death and delay poison 30
Sleeping: A successful check allows you to sleep and rest in difficult conditions, including bad weather,noise, buzzing insects, and so forth. This is important for spellcasters to recover their spells and for characters torecover hit points.
Slow breathing: You can deliberately slow your rate of breathing so that you consume less air, vital in situationswhere there is only a limited amount of breathable air available.
Ignore pain: You can ignore the effects of pain or injury. If you choose, nothing can wake you, so long as you make a successful check.
Body awareness: Conversely, you can become very aware of your physical self while trancing. This allows youto sense if your body is touched or moved in any way while you are outside of it (using astral or ethereal projectionfor example). If your physical body is damaged, subtract the amount of damage dealt from the DC.
Heal: While trancing you can speed your natural recovery, regaining hp at twice the normal rate (or level x 2 hp per day's rest).
Feign death: By exerting supreme control over your body, you can enter a deep trance almost indistinguishablefrom death. A Perception check or Sense Motive check with a DC equal to your Control Body check is required to determine that you are still alive. While in this state, you also benefit from the effects of adelaypoison spell for as long as you remain in a trance.
Try Again: Yes, for memorize and willpower uses, though a success doesn’t cancel the effects of a previous failure. No for the other uses.
Special: If you have the Autonomous feat, you get a +2 bonus on Control Body checks.
Some changes to other skills:
Concentration is a skill again. The rules as written apply for folks with no ranks in the skill. Any ranks are a bonus to all Concentration checks. Concentration is a class skill for everybody.
Fly as written is pretty confusing. If you have the ability to fly under your own power, you make any rolls against the higher of this skill or Acrobatics. IIf you are trying to Pilot an airborn vehicle, use your higher skill in Fly or Drive. For Piloting surface vehicles, roll against your Drive skill.
Knowledge: Arcane and Spellcraft each include all the features of Knowledge: Psionics and Psicraft. Just in case psionics comes up - you don't need to buy both skills. And Knowledge: Religion may likely be used as a substitue for Psi-related knowledge checks.
Use Magic Device also allows you to attempt to activate Psionic devices as well as technological ones.
Linguistists: Draconic is more complicated. Draconic isn't a single language, it is at least 4 related ones: Metallic (spoken by good dragons who refer to it as "High Draconic), Chromatic (spoken by evil dragons who call it True Draconic), Faceted (used by neutral dragons who call it Draconic Prime), and the pidgin that real dragons use with the lesser races. All 4 share a common alphabet, and the written forms are close enough to interpret with a skill roll (DC 12). The spoken forms are quite different, and the "real" draconic tongues involve high and low tones most humanoids cannot hear or produce. Understanding a different dialect of spoken draconic than the one you know requires a linguistics roll (DC 20). Humanoids with a dracoinc subtype and a bonus to perception can hear the tones outside the normal range, making the DC only 16. Without magical aid, humanoids cannot produce those tones, so they can't speak the "real" languages correctly, only the pidgin Draconic.
I have a lot of tweaks in mind for the skill system to make it more flexible and fun. Nothing is ready to roll out yet, but skill monkeys should look forward to their focus being even more useful in the future. For example, I am in favor of the "a skill for everything" rules, where you can put ranks into anything and call it a skill - rope use, hippogriff pilot, seduction, etc. The more focused a skill is, the higher the bonus you get to any related rolls (plus you can still use the "related skill" rules above). I am also putting together a chart based on the excellent book 101 New Skill Uses and a couple of similar publications.
If your character backstory is good and supports you having some skill in a certain area, I will likely grant you a couple of bonus skill points. I will also grant bonus skill points in-game if you roleplay making an effort to learn something specific.