Just drop a mealworm in front of him and he will likely eat it right away. If not, just give him no crickets, only mealworms and it won't take long (maybe a couple of days at most) to get him eating them. Be sure to either dust the mealworms in calcium or leave a little dish of calcium available to him. Mealworms are not as nutritious as crickets are. I feed my leo's mealworms and raise my own mealworms because crickets are so messy and stinky.You can occassionally buy him crickets that he will eat right away for both a treat for him and for the nutrition involved.