Anyways, here goes..
- Learn to manage your time better.
- Make your brain your hobby. When you invest interest in your brain it pays you back a much greater interest. It's the best investment you can make.
- Stay physically fit. When you're physically fit, your brain gets as much as 50% more oxygen per second every day of your life.
- Learn at least one new subject every year. Could be astronomy - go to the planetarium and drift around in the stars for a while. It could be Chinese archaeology. It could be the guitar. Could be learning about a different profession that you'd never really thought about before, like mushroom growing. But learn something new to keep the brain stimulated.
I do #2 and #4 a lot.. but keep trying to improve on #1 and #3...
P.S. As part of my continuing efforts on #4, here is my work for the day... I have heard his name before but am going to do my 'learning' today about Edward de Bono, who over the years has popularized the idea of Lateral Thinking through his books, lectures and courses and spawned a whole genre of lateral thinking puzzles!