Biodermis is the brand recommended by my derm. They make a product that can be used on the face and under makeup. It is a silicone product that you use once the site is healed and it helps with the scars.
Is it just the small circle biopsy site or stitches? Id say just a day or two. The face is an easier location than other parts of the body where clothing rubs and what not IMO.
I had skin cancer removed from my face. The plastic surgeon prescribed a product called Kelo-cote. It's a silicone gel substance for scars (new and old). Ask your doc about it, but I recommend it highly.
(Not a poster on this board, but came across this post some how) I work in Mohs surgery/Derm and we recommend anything silicone based for scar care/prevention. Also, do not let it dry out and form a scab, it's more likely to scar and will take longer to heal. Keep it moist with vaseline or antibiotic ointment until it's fully healed.