I consider CEX to be the best exchange for short-term trading. I like it for the simple and minimalistic interface, good level of security, and various payment methods available. Plus, it’s one of a few exchanges allowing margin trading (https://cex.io/margin-trading) that can considerably increase your profits. The platform has a high trading volume that shows users’ trust. I also use Binance due to the largest number of cryptocurrencies it provides. Find the place which is the most suitable for you.