Put a dab of Neosporin directly on the cut early in the day, making sure it's absorbed as much as possible before encasing it in underwear. Try to refrain from hardening for at least the rest of that day. Ofcourse, during the night you'll get erections, but dont' stroke it -- just let it lie there hands free:excl: Probably in a couple of days it'll be back to normal. The dick head heals amazingly fast.
Luke