This strategy is a great start for new traders, to understand some part of the market behavior. The idea behind momentum investing is to take advantage of market volatility by taking short-term positions. When stocks are going up and selling them as soon as they show signs of going down. Once the stock is going down, the investor closes the position and move on to new opportunities. For new traders you can watch the big news or press releases and then act on the response from the market.
Like many other strategies, you want to protect yourself when your predications are wrong. In order to do this, you may want to use stop-loss orders. This means that if the price move in the opposite direction, the deal will close automatically, when you have many trades going this helps you better manage your risks.