Use a wet q-tip to moisten the foot and then rub the food off of it. If there is a lot of very hard food stuck on the foot soak the gecko in a deli cup with wet paper towels first as mentioned. That will loosen the food so that it will more easily come off with a wet q-tip. I would not leave dried food on a growing baby's feet unless it is a very small amount because it could interfere with shedding and cause further issues and even lost toes. Some babies will run through their food and make a mess every time, but you have to keep those toes clean if the food doesn't come off after regular misting and during their normal activities.