Called arbitrage.. no one is going to tell you how to do it because you have resources like CoinMarketCap.com that show you the price of every crypto on every exchange, so it's ultimate spoon feeding.
Note though that there are two critically important considerations (plus about 100 that are still important too):
1. Trading fees and exchange fees often cancel out the profit you think you're going to get.
2. The time to transfer crypto from one place to another leads to risk of your profit turning to losing during transit.
Also, check out Bithumb. Korean trading platform, renowned for two things.. 1) having higher rates than other places, 2) randomly closing accounts and stealing crypto (happened to me for about $600 until I shamed the fuck out of them on BCT and they reached out to me to pay me the money back).
Anyway, the point is that arbitrages is HARD because you're in direct competition with fucking hundreds of hardcore multi-million dollar enterprises and hedge funds that will eat your lunch 60 times before you try to click your mouse button.
If you're interested in how people really do arbitrage right, look up "triangular arbitrage" - that's where you can still make some good money if you're a post-grad level computer science major who has been coding in C++ for 3 years or more.