Things You'll Need
Povidone iodine
Water
Bowl
Gauze
Irrigation syringe
Warning
Do not use hydrogen peroxide or alcohol; they damage tissue and prevent proper healing. If you don’t have providone iodine, clean your cat’s nose with water only.
Tip
Contact your veterinarian immediately if you notice fever, swelling, tenderness or discharge of pus from the wound. These are all signs of infection.

It's not unusual for an indoor-outdoor cat to come home with cuts and scrapes, but cats are susceptible to such injuries inside the home. Regardless of where it occurred, thoroughly clean a scratch on a cat's nose to prevent infection. If a scratch is deep and won't stop bleeding, or if it shows signs of infection, see a veterinarian right away. As long as a scratch on the nose is minor, prompt, proper cleaning should prohibit complications.
Step 1

Dilute povidone iodine with water in a small bowl until the solution is the color of weak tea.
Step 2

Dip gauze into the diluted povidone iodine. Gently clean around the edges of the scratch with the solution.
Step 3

Use an irrigation syringe to flush the surface of the scratch with the solution to remove grit and other matter. If you can't remove all the debris, take the cat to your veterinarian. Otherwise, pat the wound dry with a clean piece of gauze.
Step 4
Repeat steps 1 and 2 twice a day until the scratch noticeably improves.