I have one. And every 5 Days. She gets a lil squirt on all three sides. Just enough to have a drink. But you have to be careful bc you can overwater and then they croak! Use your best judgement. Maybe 3-5mL max
To water succulants you wait for the soil to dry out completely before giving the soil a good soak and letting it drain on its own. It needs good draining soil and pot. Do not fertilize moon cactus or the pink one on top will come off