requirements:
ar15
ammunition
wading into river
posting pics
with the rifle held at the hip, insert a siff index finger into the trigger guard (note: some guys will hook their finger or even thumb thru a belt loop to help stabilize its' position) while your offhand grasps the rifle at the forearm and manitains a steady forward pressure on the rifle.
drawing the rifle forward fires it. recoil resets it to be fired again.
light triggers make bumpfiring easier and ak's in 7.62 x 39 are easier to bump fire than ar15s as a rule.
watch where your muzzle is pointed.!!! keep it down and walk your rounds out by watching their impact points. NEVER watch your rifle!!!!! got it? never! watch where you are shooting.
only bump fire in the safest of environs.
when you get good, you will equall the fire rate of a machinegun and the best bump firers can keep their rounds on target when bumping from the shoulder.