What never said: relax.

Particularly hard to do after you've had a bad fall, or something scary happen.

Ride with better/faster riders. This has been the single biggest thing to help my riding over the years.

Armor and big tires - great confidence booster. Sucky to pedal up and fast with, but if it helps you push things a bit, go for it. Sometimes then, once you hit something up geared with that stuff, you figure out it isn't that bad, and do just fine later without.

What's your bike setup? Sometimes some very small tweaks to setup can make a big difference.

The recent trend of getting the front end of the bike/controls lower to get a bit more weight on the front tire has helped me tremendously. You aren't altering the head angle, just your position on the bike and how you are controlling your weight distribution.