This jam time is spent working on the VDD, generally in a slideshow format (essentially, a pitch). Your guidelines:
What's your elevator pitch?
What mechanics are in your game? What makes them special?
What is the art style in your game? What makes that special?
Think through the player experience.
Where are players playing this? Are they laying in their bed at night playing, are they playing it on the couch with friends?
What are they looking accomplish when they pick up your game?
Get creative! We want to see your personality come through!
We expect you to spend the first 30 minutes brainstorming and coming up with potential ideas. The rest of the time is spent developing and refining your idea, then putting it together in a presentable way. You will have 5 minutes to present and 3 minutes for questions.
Brainstorming Tips!
Set a timer for two minutes and everyone comes up with 10 game pitches. Share all your ideas, laugh a bunch. Then do it again. Then do it again.
Once you've run through that exercise a few times, talk about what bits and pieces you like and how you might mash them together to make a fun game.
The AWWapp is a great group whiteboarding tool.
Slideshow Tips
Use SlidesCarnival to find nice themes for your Google Slides!
People like colors and images: they don't like walls of text.