When a player logs in for the first time they will be automatically taken to the character customization screen. Otherwise access will be available once they login and are at the server screen
All character settings will be serialized into JSON blobs and stored on the server in Player Accounts
A very simple version of character customization should be developed with some basic preferences: Skin color, hair, underwear, sex, age, character name
A simple GUI will need to be developed
Once a player is spawned the sprites will be updated using the JSON data from the server and then synced with the clients