You should keep the cool side around 75 - 80 and the warm side 85 - 90. I have the kind of thermomets that stick to the side of the tank and have them about an inch or so from the substrate, and they work really well. Humidity wise, I try to keep it anywhere from 50 - 60%. You can tape or put a towel or the top of the cage (depending on the kind of top you have) when you have your heat light on and the humidity drops below 50%. This retains the water vapor that is evaporating from the cage. I would highly suggest putting 2 water dishes in the cage, one on the cool side and one on the hot side.