Don't become too depressed during drawdowns. Trading is a lot like golf. All golfers, regardless of their ability, have cycles of good play and poor play. When a golfer is playing well, he assumes he has found some secret in his swing and will never play poorly again. When he is hitting it sideways, he despairs he will never coming out of his slump.
Trading is much the same.
When you are making money, you are thinking about how wonderful trading is and how to expand your trading to achieve immense wealth. When you are losing, you often think about giving up trading completely. With a little practice, you can control both emotional extremes. You'll probably never control them completely, but at least don't let elation and despair cause you to make unwarranted changes in your approach. Since correct trading is boring, don't depend on trading as your primary stimulation in life.