You're asking about swing trades. A good grasp of both fundamental and technical analysis helps here. Fundamentals so you'll understand when an asset is likely to hit a period of increased growth rates, and technical analysis to figure out when and how to sell (and rebuy) the inevitable correction.

Read up on literature about the three terms and study it.


Don't listen to some random dweebs on the internet. They'll just try to manipulate you or pander off worthless advice.