Online trading is great way for serious investors to make money, but inexperienced traders often wind up with big losses. A good set of instructions can minimize the risks and save months of expensive trial-and-error learning.Day TradingDay Trading had its heyday during the bull market of the 1990's. All the amateurs have since dropped out, but day trading is still being practiced by professionals. There are fewer opportunities in the current market, but skilled investors can still find them if they know what to look for.