List of free things to do to get tickets.

1. Post a screenshot
2. Recommend a game.
3. Facebook connect to Steam
4. Play a demo game.
5. Post on someone's Steam profile
6. Get caught on fire in Team Fortress 2 and fall in water to put yourself out.
7. Join the Summer Camp official Steam group.

8. Download and watch a trailer.

9. Build a wishlist of 10 items.
10. Post a video in Steam.

At this point, you could have 3 prizes!

11. Post a comment on a friend's screenshot.