Remember to get 8 hours of sleep a night.
Get at least 30 minutes of exercise a day.
Don't drink over 2 cups of coffee a day.
Don't drink soda at all if you can. If you have to just once every other day or three.
Don't spend more than 3 hours a day on your phone or computer.
Don't watch that much TV or play video games that long either.
Look for a job where you won't hurt your back or your ears.
Don't listen to music too loudly either.
If get in a wreck go straight to the emergency room even if you think you're fine. It takes up to 24 hours for muscular-skeletal injuries to set in and this can be the difference between a few days to recover and a lifetime chronic injury.
Don't masturbate more than twice a day. Life passes you by while you are sitting at your computer looking at porn.
Don't complain to other people about something you read or saw on the internet. You gain nothing from this, only lose respect in the other person's eyes.
Get some proper furniture and a proper bed that will let you really rest when you need it.
You should learn what the glycemic load of your diet is.

Put your health before almost everything else. Even if it means giving up things you think define who you are. Because once one part of your health is gone it's easy to lose others, and you're down a road that is very very difficult and long to come back from, if you can ever do it. Best not to take that turn to begin with.

Most all be a good person who says only what needs to be said without griping too much, or without indulging pointless speculation. This will make other people think you are more noble and dependable, and you will like yourself more for it because it will be the truth. And if something tragic does befall you then your friends and family will be there to help you instead of withdrawing.