Download the Roleplaying Guild Guide. Print out the character sheet and inventory tracking sheet on the back pages.
Create a 1st level character with 20 point buy. Follow this guide. Your starting gold for society play is always 150gp.
Choose a faction from the Guide to Organized Play.
Choose 2 traits for your character. Traits may be from this list of basic traits, a faction trait from your faction in the Guide to Organized Play, or from any other legal source. You may choose only one trait from each category.
Step 6 (optional):
Register your character on Paizo.com and get a Pathfinder Society number.
Sign up for games.