When I had Hyla squirella (3-4cm) I offered them 3-4 small crickets/tenebrios 2-4 times a week.
But this was no strict rule, I just put them in a box with some crickets/tenebrio and the frogs would start eating them. After each one eats the quantities I said before, they normally would start losing interest in the food and becoming more worried about leaving the box. That was when I used to pick them up back to the terrarium.