I personally feed every other day for my adult male panther, and he gets around 16 large crickets and a couple worms every feeding, but he never really gains weight at all it's ridiculous he is extremely healthy and is a stupidly good eater. If I feed roaches that day he eats as many roaches he that he wants, usually ends up being 4 adult males and a couple silkworms or two wax worms.
My foster veiled is technically almost an adult, she was severely undernourished in the beginning of her life though so she gets fed every other day also but more than I would ever feed a female. She eats around 15-16 medium crickets, just hoping to get her to grow some. She refuses to eat anything other than crickets and silkworms so right now I am growing silkworms out for her and my panther boy, Ryker, so that they will have some of their favorite worms.
Do you have a baby/juvenile chameleon? Usually you feed them every day and feed them as much as they would eat. Considering a young chameleon grows to around 18 inches or larger (if they are a veiled or panther) in around a year they need large quantities of good quality food. So I would only stop feeding a young chameleon when they don't seem interested and then take that number as the general number to stop feeding at.
Are you feeding any soft bodied feeders? Like silkworms? Or hornworms?