It's a volatile market out there, but that's no reason to go and hide in a bomb shelter with all your cash. Sometimes simple trading strategies are the best, and you can do more harm over-thinking your portfolio than you can by following the clear strategy you laid out for yourself months before the May swoon.

Here are three examples of simple investing rules that work in any market that can help you focus on the opportunity right now, and build a portfolio that succeeds no matter what happens on Wall Street:

Alas, I had to say good-bye to an old friend Nuance Communications (NASDAQ: NUAN). This is a technology company that specializes in speech-recognition software and digital-document solutions, and it competes with the likes of IBM (NYSE: IBM) and Microsoft (NASDAQ: MSFT). It's a cool business, although it grows by acquisition, so you do have to watch that part a bit (i.e., checking the GAAP vs. the non-GAAP numbers, cash flows, etc.). The 52-week high on the stock is $22.55; the 52-week low is $9.31. I remember thinking when the stock hit the high that maybe it was time to sell out. I wish I had. But I had confidence in its long-term future. I still do.

As we all know, though, everything has changed. The financial crisis is bringing everything down to irrational price levels. Shorting is one of the only ways to make money. And capital preservation is now on the top of everyone's agenda. That's what my sale of Nuance was about. It's one of the few stocks I owned that still showed a profit. I bought in well below $10 per share. I sold my shares on Friday for $10.13. I can always buy them back when things settle down. I should have sold a lot earlier during the downtrend; I could have generated more proceeds.

And that's one of the reasons why I'm writing this post. I want to tell you why I didn't try to raise some cash by selling Nuance at a better time period. I want to help you not be the idiot that I was. Okay, ready? Here goes. I didn't sell earlier because I held Nuance in a taxable account and didn't want to deal with paying the capital-gains taxes in '09. Like they say, if you get too cute about avoiding taxes, don't worry, you won't owe them because you'll have no profit. And that's a great way to get rich, of course (big sarcasm there, in case you didn't notice).