While your home game might use rule variants or house rules, Pathfinder Society sticks strictly to the official rules, and also has some restrictions on what content is available to you during character creation. Not all of this is immediately obvious and took me a lot of clicking around and cross-referencing web pages to sort it out, so I’ve clarified the process and restrictions below.
Owning the Source Materials
Pathfinder Society requires you to own a copy of anything you use outside of the Core Rulebook. This can be an official PDF from the Paizo site or a physical copy, and you must be able to show proof of ownership at the table. This means either bringing the physical book, bringing printed pages from an official PDF with your name watermarked on it, or a printed copy of the rules text alongside proof of purchase. Using Archives of Nethys alone does not qualify.
If you’re using Demiplane’s Pathfinder Nexus, you’ll need to show proof of ownership alongside the rules text.
Details are explained further on the Character Options page. Scroll down to “Using Options: Resource Ownership”.
Step by Step
This section expands upon the Character Creation page for Pathfinder Society. You should also check the Pathfinder Society Character Options page to check for possible restrictions, adjustments, and interpretations relevant to the character options which you’re considering.
Any books not listed on the page may not yet be sanctioned for use in Pathfinder Society, so that shiny new release may not be usable yet.
Start Building Ability Scores
PFS uses the default rules for ability scores, so you start from 10 in every ability score and apply boosts and flaws as you build your character.
As of this writing, the documentation for Pathfinder Society stats that it still uses the original Voluntary Flaws rule which was reworked in the errata issued alongside printing #4 of the Core Rulebook. Be sure to check the official documentation for the latest rule.
By default, you have access to the ancestries in the Core Rulebook plus Leshies and Kobolds. Other ancestries must be unlocked as a Boon by spending Achievement Points (more on those later in this article series).
Select Home Region
Your home region and ethnicity can offer access to some Uncommon options. See CRB 420-431 and Lost Omens: World Guide.
All Pathfinder Society characters are literate and speak Common (Taldan) as well as any other languages granted by their ancestry. All Pathfinder Society characters have access to all common and uncommon modern regional languages. Regional languages are defined on page 432 of the Core Rulebook, however Pathfinder Society characters are not limited to the 9 regional languages on that page. All Pathfinder Society characters begin with one additional Regional language.
You get whatever languages your ancestry offers, Common if your ancestry doesn’t give it to you, plus one additional regional language.
You have access to all of the backgrounds in the Core Rulebook. The Pathfinder Society documentation makes no mention of backgrounds from other source books and I don’t see a way to get access to other backgrounds via Boons.
Choose a Class
There doesn’t appear to be a limitation on rarity of classes as far as I can tell, so you’re fee to pick any published class.
Determine Ability Scores
Total all of your boosts/flaws and finalize your ability scores.
Record Ancestry and Class Details
Record all of your ancestry traits, your class features, and your feats.
You start with 15gp to spend on equipment. You can purchase items according to the Purchasing Guidelines, which at first level typically means Common level 0 items from the Core Rulebook.
Fill in all of the math on your character sheet.
Remember that evil characters are not allowed.
You’re only required to choose a deity if your class depends on it (clerics, etc.), but you can gain benefits from worshippin certain deities or religions, such as access to items.
You must be an adult. The iconic Summoner is not allowed to join Pathfinder society.
Determine details of your character’s name, preferred pronouns, and appearance.
Get a Miniature
You need a representation for your character on battle maps. If you’re playing in person, you need a miniature of some sort. If you’re playing digitally, you need an image which you can turn into a token.
Update Your Character Page
Return to the My Organize Play page. Find your character (assuming that you created an entry for them already as described in the previous page), and click the “Edit” button on the far right.
Fill in the form fields to the best of your ability. This is not a replacement for your character sheet, and the form hasn’t been updated since 1st edition.