I think it really depends on how much you want to play. I've seen some people talk about percentages, but I think a good idea is to take your total deposit and divide it by the number of times you want to play in a week, month, or day. It's easier to organize yourself that way.
Being able to stick to your capital whether you’re winning or losing is the smartest decision to make when it comes to gambling , the intention should go beyond just starting, it should have been made right before you started gambling to set a limit which is tied to your capital. As a gambler or an intending one, you must also be good at emotional control while you enjoy the game. Do not allow your emotions to sway you from your targets else you will keep chasing 'just one more win’ and you will eventually lose everything you gained.