its really easy.
this guide is from an empty system
Take the pads out, find a suitable object to wedge the caliper pistons out (like a big allen key or block of wood))
Undo the resevoir bolts and take the lid off
now fill it up with royal blood untill full
undo the bleed nipple on the caliper a turn or two, squeeze the lever to force the fluid through. BEFORE you let the lever out again, do up the bleed nipple, this will suck the fliud though the system.
Keep doing that BUT MAKE SURE THERE IS ALWAYS FLUID IN THE RESEVOIR!! If you let air in, you need to start again.
If that isnt working properly just undo the bleed nipple a bit more and let gravity suck the fluid film, again you need to make sure the resevoir is kept full.
once the caliper and hose is all full with no air (squeeze the lever with the bleed nipple closed to force any air out) fill the resevoir to the brim and fit the lid.
Jobs a good'un