The title says it all!
I'm pretty sure there must be some veterans among the near 400 participants. So, any advice for the newcomers?
Before the jam:
1. If you want a team member, don't just wait for one, look for them too.
2. Make sure everything you plan to use works before the jam starts.
3. Practice. What you make beforehand might not be allowed to be entered, but it still readies your brain.
During the jam:
4. Communicate with your team members. Everyone should know the progress being made as often as possible.
5. When you begin to sleep, set your alarm for a specific number of hours you would like to sleep for.
6. Cook and eat your food fast. Since this isn't a local game jam, bathing is optional, but if you do be quick.
7. What you make does not have to be optimised, just make sure it doesn't crash or drain the CPU drastically.
8. Don't try to implement anything you haven't done before. This could lead to poor or half-baked results.
After the jam:
9. Don't worry! As long as you did your best, don't beat yourself up over your submission.
10. Be proud of what you accomplished. Everything is a learning experience - there's always next time.
To summarise in one sentence: The time to learn is before the jam, not during, leave professionalism out the door and have fun.