About Trading: http://www.marketwatch.com/story/10-...3?pagenumber=1


3. Use limit orders, not market orders

A market order simply tells your broker to buy or sell at the best available price. Unfortunately, best doesn’t necessarily mean profitable. The drawback to market orders was revealed during the May 2010 “flash crash.” When market orders were triggered on that day, many sell orders were filled at 10-, 15-, or 20 points lower than anticipated. A limit order, however, lets you control the maximum price you’ll pay or the minimum price you’ll sell. You set the parameters, which is why limit orders are recommended.


8. Never act on tips from uninformed sources

Most pros know that buying stocks based on tips from uninformed acquaintances will almost always lead to bad trades. Knowing what stocks to buy is not enough. You also have to know when to sell, and by then the tipster is long gone. Legendary trader Jesse Livermore said it best when he wrote this about tips: “I know from experience that nobody can give me a tip or a series of tips that will make more money for me than my own judgment.”

If you can’t trust your own judgment, you may want to avoid day trading altogether.

#3 is important for everyone, not just Day Traders! #4 warns against using house margin accounts. I'm under the impression that DIY e-trading sites make those look more attractive than they should be....