We'll need more info to really help you. Assuming it's from the Mojave desert, then you have a wandering type lizard that's not happy in a small, confined space. You will need to set it up in a very large, flat tank or enclosure with lots of play sand at least 1-2" deep. A large tube partially burried on the cool side of the tank will help it feel secure. Under tank heat is not needed or recommended, but a UV A&B light above on one end along with a 50-70W heat light is required. The area under the light should get to about 100F. Place a flat rock here, but not so big that it squashes it if it digs under it. You should place a heat barrier (PVC pipe, rocks, bricks, etc.) to separate the sand in the tank to make sure there are hot and cool sides in the tank. Plant matererials not needed, but I always put lettuce in just in the lizards don't eat the crickets...don't want the tables getting turned.
As for food, crickets are fine for smaller ones, but these are lizard eaters...so you'll need to supplement the cricket diet with bigger, live prey items, like Uta's or pinky mice if you want it to prosper. Only do this after the animal is good and heated, and very alert....otherwise it will not eat them.
Watering....Like most desert lizards, you don't put water in the tank with these guys. Instead I recommend placing it into a large glad container filled with only 1/4" of water. Slightly Mist the lizard as it goes in and leave it in there for ~10 minutes. Do this two or three times a week and it will not get dehydrated.
Enjoy,
Roger
