1) Learn your limit(alcohol wise) before you turn 18.
2) Learn what types of alcohol you actually enjoy.
3) Learn how to drive (legally)
4) Learn how to manage your time wisely.
5) Have a best female friend
6) Share a relationship with a female
7) Get a job to have spending money independent from your family.
8) Experiment with sexual stuff so your not clueless but on your own level.
9) Stay current on trends and major news.
10) Most of all have fun, and don't break and laws you will suffer from in your adult life.

