1. Don't think about love/sex
2. Don't think about games
3. Don't think about friends
4. Don't think about cars
5. Don't think about technology
6. Don't think about anything that is interesting and would waste your time. I.e. dont think about anything
7. Keep music to a minimal
8. Remove anything distracting in your room (I've done this a month ago...)
9. When doing work that requires the computer and internet, just to focus on your work and dont be tempted to browse the web or watch a movie, listen to a song or play a game
10. Get motivated. Stick notes all over your room. With words or phrases like "it is fun to study", "time is running out", "study well and u'll pwn everyone", "it's the HSC !"