Do it when they are contented (like after a meal) and distracted by a toy or anything else they like. Ideally, you should give your dog an insulin shot during or after a meal. The easiest method to give your dog an insulin shot is to provide them with this injection while they are distracted.  If your dog is uncooperative while administering an insulin shot, you can seek the help of any other person. This other person can hold and keep the dog stable while giving them the insulin shot.