You can offer food everyday. Offer a amount that will get eaten in first 5 - 7 minutes of introduction. Might take longer if animal is shy, or timid. Chameleon will slow down or stop feeding when full. Adults can skip a day or two, but I like to offer at lease one insect item per day with my adults. You want them fed, but not to the point that they start looking obese. With Veils you can watch their tail base. Rail thin - feed more / plump and round - diet