I've got a ornate uromastyx and she is about 6 months old. I'm not even close to be like an expert, this is my first one. But from what I learned about where I got him (not a pet store) and some other people on here this is what I know. The majority of the food they eat is vegetables. Chopped up carrots, dandilions, broccoli, turnip greens, and mustard greens. (I'm sure there are many more) The basking temperature has to be around 105-115 degrees. The cool side of the tank should be at like 85-90. I'm not sure about what kind you have but mine is brown with orange on the head, the sides of the body, and the tail. If you have a mali, they get much larger than the ornate. I really don't know too much else about other types. Mine will eat meal worms, the tiny tiny ones. She definitely is interested in crickets, but they are much too fast for her. Mine also loves water, which, apparently, is not normal. haha so I'm not too sure about the attitude of your little dude.
Well, that's about all I know.