You can take the "courses" that javabytes mentioned (each one is worth 500 points and there are 4 of them), or you can e-mail them and ask them about the promo they are running now. It is 40,000 SB points you get if you sign up a new account with the promo code and fly before 8/31. I signed up in January with no code and I was almost at 100,000, so I thought it would be a nice boost. They said they couldn't give it to me, but they did give me a "goodwill bonus" of 10,000. So, try e-mailing them (if you signed up with no promo).