Other Ideas for promotion.

Of course, you arent limited to just trying to promote at college. You are in living in a big city. There are alot of other people other then students there. You could promote at Football or Rugby games, concerts, put posters up around the place, or leave flyers in pubs. Get some stickers printed with your bonus code on it. The world isyour oyster, and your only limitation is you, and your imagination.

Organise a poker game in a pub. It has to be free to enter, for legal reasons, but give away prizes and make sure everyone there knows about your bonus code.
If you give someone a $50 poker account for winning, you can do it under your code, pay $50 into his/her account and then you receive $65 at least for referring him. You gain $15 for giving your code out to lots of new people, and having a good night out.

If you have HTML skills then you can really open up your business. Build a poker website, with tracking links, rather then codes, and instead of going for 10 sign-ups a minth from your local area, you will be marketing to milliosn of people from around the world.

Poker is the boom business at the moment and you can be part of it.