There's a few different strategies you can look into, e.g. pingpong, rollercoaster and bollinger bands strategies. You will learn to identify when the market is moving into a position that makes buying favourable, or moving into a position where you should sell. The simplest strategy is to buy at the bottom of a dip, and sell at the top, keep repeating this with small amounts and you'll eventually work out roughly when these will be. Expect to lose money on your first few trades.