Water, witch hazel (if you're getting generic make sure to read cause its usually more percentage of alcohol than WH) melted coconut oil, a couple drops of tea tree oil depending on how strong yours is. Your dogs ears will smell good too!
DIY - Dog ear cleaning -- Dogs with long, floppy ears are frequently the victims of ear infections. To avoid chronic ear infections, it's best to make routine ear cleaning part of your dog-care schedule. Many ear-cleaning .