1) Get Ben Tan's book "The Complete Introduction to Laser Racing."
2) Buy the Advanced Laser Sailing DVD, but don't be intimidated by the fancy boat handling. Just to let you see the stuff you can be practicing.
3) Try to get out practicing with a friend or alone.
4) Race as regularly as you can. If you have not been practicing, then try to get out sailing early and/or stay late and sail some more.
5) Talk to as many sailor as you can after racing. How did they do? What did they do right? What did they do wrong?
6) Ops, but those 5 will keep you busy for a little bit.