You need to clean the wounds with a mixture of Peroxide and water. Thoroughly wash it and make sure it is dry. You can put a antiseptic ointment on it such as Neosporin. Wrap it with gauze and tape it as well.
You will need to keep him from licking and scratching it. A clean white baby sock cut down the sides and taped on should keep him from it. Though you may need to get him a dog collar (Looks like a funnel) to keep him from chewing if he is persistent.
Clean and check the wounds twice daily. If it looks infected, smells bad or is seeping pus you will need to have him examined by his vet for infection so you can get antibiotics to clear it up.