Some resources for you as a player:
The Flaxseed Pathfinder Lodge and Castamir's Flaxseed Station - where you can find a TON of resources about playing Pathfinder & Starfinder Society games in Play-by-Post format!
I STRONGLY advise newer players to Play-by-Post gaming to check out the amazing resources that The Flaxseed Lodges have put together. In fact, rather than re-post all of the links that are there, I'll just add a few beyond the ones already referenced above:
GM Hmm's profile page with tons of great links (some of which I also have below)
How to create a PFS character for PbP - Good basic info!
DH's Guide to PbP - Especially his "advanced" tricks!
PFS Session Tracker - A fantastic online database for you to keep track of what you've already played and GM'd. I use this myself and highly recommend it!