Sorry I'm new here but can I start making the game now or do have to wait until it starts?
"As for ideas, you are free to plan out your game before the jam starts."
I think that means you have to wait until it starts to start actually making it :)
Kalyen is right. You can start planning your game whenever you feel like it but you can only make it during the jam period.
Just to add, certain premade assets are allowed as well. Generic things such as a character controller, but nothing which is unique to the specific game. So no implementing mechanics and stuff before the commencing period!
How about a tileset, Is that ok?
Yes that should be fine, as long as you explicitly state what were premade
