I generally give a quarter sized amount of vegetables daily so the nutrition is better balanced on a daily basis. However, you could give a larger amount every few days if you'd prefer that. You'll want to start slowly, only offering it once or twice a week, and then moving it up to the desired amount. Remember too though, that the amount you should offer varies by the weight of your hamster as well. I wouldn't offer the same amount of veggies to a 200 gram Syrian as I would a 125 gram one. Offer as much as you think is best as often as works for you
best wishes
Btw, no such thing as a stupid question. All questions are valuable and deserve an answer!