A dermatologist should be contacted for a scalp lesion, you have to know what you are dealing with before you can treat it. Scalp lesions could be anything from a fungal infection to skin cancer
Do not use any hair products such as gels,mousse,or hairspray. Use a solution to clean the infected site containing 50% peroxide and 50% water. Then apply Neosporin to the infected site.
Being superficial,you only have to clean it with water and soap... it heals by itself. If it's more critical, press a piece of fabric against it and go to the hospital.