We've all spilled blood in the backcountry: Your skin surfed some scree, or your knife sliced your thumb instead of the cheddar. For minor cuts, Matt Phillips, a Wilderness EMT based in Ketchum, ID, recommends an infection-thwarting wash with soap and water, a smear of antibacterial ointment, and a bandage. For gushers, he suggests the following.
Several sterile gauze bandages (or something absorbent, like a clean T-shirt), elastic bandage (or strip of clean cloth), latex gloves (if tending to someone else's cut).
Hold gauze firmly over the cut and elevate the injured area above the heart. Unless you've severed an artery, direct pressure will staunch the flow within 20 minutes. Then use the elastic bandage to strap a 1-inch wad of gauze over the cut. If blood saturates the bandage, cover it with more gauze as replacing it can interrupt clotting. Don't wrap it too tightly; tingling or numbness in your extremities means you're disrupting circulation.
A few hours after the bleeding has stopped, remove the bandage and replace it with a Steri-Strip. Available in most big pharmacies, these handy adhesives "stitch" together even the deepest gashes. Keep the area clean and replace the strips daily to prevent infection.