If it's wet, dry it, and if its dry, wet it.
After your tattoo procedure your body will weep a small amount of serum or "blood plasma". Its mostly water with a small amount of proteins, glucose, clotting factors, and electrolytes. blood components
The idea is to clean all of that off of your skin during the healing process to prevent your body from forming a scab.
If traditional plastic wrap was used, remove it in two hours and clean. Use a warm water and a non fragrant soap, Cetaphil is a good one but any will do. After cleaning the entire area, use a warm wet paper towel to remove any detergents from the soap, then pat dry. Apply a small amount of ointment and work it into all areas of the tattoo evenly. It doesn't really matter the brand a&d, aquaphor, any tattoo fancy stuff, but I prefer Purple Glide. Wait 30 minuets for the body to sweat out any excess and wipe till its completely dry. Twice a day is usually enough but if its dry to the point of irritation, repeat the whole process. One thing you don't want to do is to simply apply the ointment without washing the area and your hands, and never add a layer of ointment. Always wipe till its dry again. Do this for 7 days then switch to any old lotion or ointment to keep your tattoo looking bright.
A breathable barrier film may be applied after the tattoo process to avoid the hassle of this cleaning regiment, and can be worn for up to 7 days. I use Tegaderm but most will perform the same as long as they are applied correctly. This stuff is ideal in most cases due to the fact it keeps the tattoo area from dirt, lint, bacteria and any other environment issue from the healing process. Just be mindful in the shower so the bandage won't prematurely come off. To remove the bandage start by peeling a top-corner of the film and run warm water under the film allowing it to fill slightly, then with clean hands rub the soap inside the bandage breaking the gluebond. Clean the area completely and use your lotion/ointment like stated above.
Do not soak your tattoo, pick your tattoo, spray perfume on your tattoo, expose the tattoo to direct sun, touch your tattoo to any non sterile surface (gym, dirty bedding, couch the dog sleeps on). Do not apply sunblock or anything else besides the ointment to the tattoo. Do not take extensive showers longer than 30 min, or swim in the ocean/lake/river. Do not wear anything tight or restrictive over the tattoo, do not wear anything other than cotton, bamboo, or natural fabrics (no polyester or blends) Do not rely on other tattoo aftercare methods, you trusted me with the tattoo, trust me with the aftercare.