Bathe it every so often, keep it away from any heat, and do NOT put tissue over it, as the particles in if could cause infection. The best thing to do is go to your doctor
wrap it as tightly as possible in a bandage or gauze it will hurt but you should keep it dry so if it bleeds switch the bandage do not put any liquid except antiseptic or numbing sprays dont touch...
depends where.... street or a business or an online ''company'' usually street vendors will sell you something that looks real or authentic and sell you something that is either stolen, broken, or...