If the strategy is within your risk limit, then testing begins. Manually go through historical charts to find your entries, noting whether your stop loss or target would have been hit. Paper trade in this way for at least 50 to 100 trades, noting whether the strategy was profitable and if it meets your expectations. If it does, proceed to trading the strategy in a demo account in real time. If it's profitable over the course of two months or more in a simulated environment, proceed with day trading the strategy with real capital. If the strategy isn't profitable, start over.
The first key to successful swing trading is picking the right stocks. The best candidates are large-cap stocks, which are among the most actively traded stocks on the major exchanges. In an active market, these stocks will swing between broadly defined high and low extremes, and the swing trader will ride the wave in one direction for a couple of days or weeks only to switch to the opposite side of the trade when the stock reverses direction.
In addition to knowledge of basic trading procedures, day traders need to keep up on the latest stock market news and events that affect stocks—the Fed's interest rate plans, the economic outlook, etc. So do your homework. Make a wish list of stocks you'd like to trade and keep yourself informed about the selected companies and general markets. Scan business news and visit reliable financial websites.