To stop a nosebleed:
Sit down and gently squeeze the soft portion of the nose between your thumb and finger (so that the nostrils are closed) for a full 10 minutes.
Lean forward to avoid swallowing the blood and breathe through your mouth.
Wait at least 10 minutes before checking if the bleeding has stopped. Be sure to allow enough time for the bleeding to stop.
It may help to apply cold compresses or ice across the bridge of the nose. Do NOT pack the inside of the nose with gauze.
Lying down with a nosebleed is not recommended. You should avoid sniffing or blowing your nose for several hours after a nosebleed. If bleeding persists, a nasal spray decongestant (Afrin, NeoSynephrine) can sometimes be used to close off small vessels and control bleeding.
Things you can do to prevent frequent nosebleeds include:
Keep the home cool and use a vaporizer to add moisture to the inside air.
Use nasal saline spray and water-soluble jelly (such as Ayr gel) to prevent nasal linings from drying out in the winter.