When choosing a crypto exchange, make sure that is has a good reputation because there are a lot of crypto exchanges in the past where in turned to scam and they steal the funds of all the users. A good crypto exchange should also have legit volume where you can easily enter and exit in a trade. It is also should have good support because if it has a slow support then for me it is not good crypto exchange and it should be avoided in order for us to have convenience when doing trading.
Choosing a exchange is a skill wherein in take time for you to master that kind of skill. I experienced to use a crypto exchange that have bad service and it is the reason why I decided to always do a research before opening an account in a exchange. What I also like in an exchange is there should no verification wherein the KYC is not mandatory because I do not like uploading my verification online.