The specifics on joining next year haven't been fully established as we are going to make some changes based on what we learned this year.
It will most likely have a game jam and a google form. Filling out the google form will be the most important part in order to join.
Here is a link to last year's jam:
https://itch.io/jam/queer-games-bundle-2021
Next years format will be mostly similar to this.