Good day as I am new to the crypto world What is really the way to make $ in in crypto ? such as Bitcoin or other coins?

I understand as i have some invested. in my wallets the values go up and down, so you can cash out or sell when value up?

do you just buy and sell currency as the markets move up and down? or what other ways to make $ with crypto?
do you transfer bitcoin over to other websites etc?

or what should i be focusing on? thanks

just like to know what all the experts do?