Mike, Could easily go on and on, but I will make only one point here. Learn how to play both sides of the market (long/short) with near-equal comfort. Without that, you will be in for extended periods of time where returns are low or negative. And if your lifestyle has to be curtailed as a result, it's the type of situation that can result in increased risks-taken, and that's usually not a good plan.
Solid DD combined with timeliness and conviction is a recipe for profits.