Alon, one of the founders of Invested.in just wrote an article on his personal blog with some great lessons in promotion.  I recommend you go check it out when you have a chance.  It’s a bit long, but definitely a worthwhile read.  I would try to summarize it here, but he already did it best:

When promoting an event, just like promoting a startup, a fundraising campaign or really anything, all you really need to understand is who the target audience is, and why they care.  If you can get that initial crowd (validation), find your die-hard fans (evangelists) and use them to bring in that target audience (customers), the game’s over and you’ve won.

Read the whole article here:  http://www.allidoispunk.com/crowd-punk-lessons-promotion/