After considering some of the most important lessons I've learned thus far, my "note" would be in the form of a list and it would go something like this:
1. Be true to yourself.
You are who you are, inside and out. Embrace it; don't apologize for it.
2. Don't worry about what others think of you.
People's opinions and thoughts of you have nothing to do with who you really are. Some are going to pass judgement no matter what you do, so do what you feel is right.
The people who really love you will support your decisions, backup your fights, and dance at your parties.
It's your life - live it!