How to care for a red top yule cactus?

Hi, i just found out that that my cactus is a red top yule cactus. unfortunately there is no place in my town that can tell me how to care for it. It is very small and in a smaall pot. I couldnt find out how to care for it on any website. Anyway, how much water do i need to give it? (ml,l) its in a small pot by the way. How much sunlight does it need? do you have any other tips? when should i give it a bigger pot?