I have a pretty nasty scab in my nose almost all the way around the opening. very sore. what is the best way to treat it?

Don't pick: Keep your hands and fingers away and try to stop blowing your nose or using tissues/handkerchief. Apply vaseline or Bacitracin and let this heal, which it won't if you keep "fussing" with it!

Scab in the schnoz : You should see a physician about this 'scab'. This needs to be visualized since it can be something besides a persistent sore.