First aid
Keeping blood inside the body can be done using a piece of cloth (which soaks up blood) to apply firm pressure to the bleeding area(s).  This "direct pressure" is the simplest and most effective way to stop bleeding.  Others such as a tourniquet, are taught in first aid classes.  If a first aid kit is not there, a cloth "dressing" for direct pressure can be made from ripped or cut clothing.  Traditionally it was taught to use the patient’s clothing, if practicable, as any bacteria will be familiar to the patient.