Because you have a Veiled Chameleon who is under a year old i would recommend feeding about 8-12 crickets a day. With the supplementation that they require. My veil eats about 10 crickets a day plus a leaf of mustard greens. Based on his size i want to say he is around a year old. However, i do not feed my animals until they are full, i keep all my animals fed so that they are very healthy and not getting overweight. Also when i am working on training one of my animals i tend to keep them keen in the summer months ( keeping them ever so slightly hungry) so that they are willing to work with you. Am i saying to starve your pets god no! haha But i do keep mine slightly keen so that they do not get used to the idea of being able to do whatever they want ( acting like brats). Its a simple training method that is used by almost all animal trainers. they associate you with food, but only if they cooperate with you. Therefore, because food is positive, you are also a positive thing via association.