Flour will work too if you don't have corn starch
Apply styptic powder to the bleeding tip of the dog's nail. If styptic powder is not available, use corn starch. If corn starch is not available, use flour. This will promote blood clotting.
Allow the styptic powder (or styptic powder substitute) to take effect for about 30 seconds. Then, reapply some additional styptic powder if necessary.
Apply pressure with a clean paper towel or gauze pad once the dog's bleeding has slowed significantly.
Wash the paw with anti-bacterial soap (i.e. Dial) once the dog's nail has stopped bleeding. Use luke warm water - hot water or cold water will shock the nerve-rich exposed quick in the dog's broken or clipped-too-short nail.
Pat the paw dry with clean paper towels after the dog's injured nail and paw has been washed,
Pour Betadine over the dog's broken nail and allow the Betadine to air dry.
Apply a dab of Neosporin or Aantibiotic ointment to stave off infection in the dog's injured nail.
Apply rolled gauze to the foot and ankle in a "figure 8" pattern. Wrap over the toes to keep the dog's broken or too-short nail from becoming contaminated with bacteria or dirt.
Cut the excess rolled gauze after two layers have been applied to the foot in the form of a bandage and tape the end of the gauze in place.
Wrap the dog's food with a self-adhering bandage, using a "figure 8" wrapping pattern around the dog's foot and ankle. This creates a more durable walking bandage, as the gauze will quickly degrade from walking.
Apply an Elizabethan collar, also known as an "e collar" or "lampshade" if the dog insists on biting or licking at the bandage.
Repeat steps twice a day until the nail has grown out, covering the exposed quick of the dog's injured nail. This usually takes a couple of days, or even a week or more. When the dog's nail is no longer sensitive during washings and handling, the bandage will no longer be necessary.
Read more: How to Stop a Dog's Nail From Bleeding | eHow.com
http://www.ehow.com/how_4621458_stop-dogs-nail-bleeding.html#ixzz0sIcfvrFz