How to make money in bad economy through Stock Market

I am not a professional to the stock market, not even know a little bit about the stock market, but I began trading right after the stocks fall down. My basic strategy was to look at which stock is dealt more and try to buy that, usually the stocks which declared their gains / losses during the last year are a good candidate. Then you just need to wait for that shock to fade away from the market and the stock price goes to its original price again. Within two or three days you simply are making a great money. This method doesn't need that much time and knowledge, just buy some, sell two or three days after and you have some extra cash.