I've used pressure bleeding and vacuum bleeding and even gravity bleeding when filling completely dry systems.
The easiest way I found was to get a large syringe from the farm supply store and push a syringe or two full of fluid through each bleeder port(with all the others closed at the same time)toward the master cyl. This pushes the air in the natural direction it wants to go. Works especially well when using DOT 5 fluid which likes to trap air when agitated.
