What is a technique used to stop bleeding?

The usual method is direct pressure, which will stop blood flow while clotting begins. Bandages are used to prevent the clots from opening up, and not to "absorb" the blood.

For serious injuries, compressing the arteries or veins supplying the tissue can stop the bleeding. One well-known method is the tourniquet, which tightens (sometimes by twisting) to compress the tissues around the blood vessels. Note that this only works if the bleeding is "below" (further down the bloodstream) than the tourniquet.