the fronts you can do as normal "pump the pedal and let the pressure do the rest" but the reare need the pump to be primed up and 3 peole in the real world

turn the ignition to positio one so that the pump primes up first
this will build up the pressure in the rears
you need to open the resivour cap and one person needs to stand there ready to top up the fluid
the second person needs to be sat in the seat with a toe on the brake pedal to run the system
and then the 3rd person at the rear opening the bleed nipple
the fluid will just run out and you've got 20 seconds worth of fluiid running out to clear the lines properly before you HAVE to turn the ignition off to stop the pump overheating
thats why you need someone at the front topping it up
doing it the normal way does nothing as you HAVE to have the pump to get the fluid to the rear

if you run out of fluid then you also run the risk of getting an air lock in the abs valve block, and they can be difficul to get out