Take a piece of kibble or a treat and put it in one of your hands. Make a fist with both hands and hold them in front of your dog and have them pick which hand the treat is in. If they try to mouth you or scratch at you, it's a good time to reinforce some manners.
Have your dog stay, or have someone distract them, while you go hide in a closet or behind a piece of furniture. Call your dog and see how fast they can find you. Of course, a tasty treat is a great reward.