When you have been reduced to 0 Hit Points and are Bleeding Out, but it is unsafe to lie down on the ground or relocate to a nearby safer area, you can go down onto one knee, lean against a tree, or otherwise take a posture that indicates you’re not able to fight.
If anyone comes up to you with intent to attack you, you can call out “Bleeding!” to inform them that you are in fact Bleeding Out and can’t fight back, which should inform them that they don’t need to hit you. (They may still decide to Execute you, however.)