10.) Take care of yourself on a regular basis. This doesn't just mean going to the doctor and dentist regularly. Reconnect with your childhood, keep up an active social life, pamper yourself occasionally, and don't feel guilty about downtime.
Some people may perceive playing to be frivolous, but they're missing the point. You need occasional periods of recreation in order to avoid burn-out and to keep caring about what you're doing with your life. Slow down and smell the flowers occasionally! Play is more than something "extra" -- it's the ultimate pillar on which your life rests.