I just recently bleed the air out of plane brakes. I was taught to use a pump oilier can with rubber hose attached to it full of special hydraulic fluid for plane brakes. I squeezed the oilier and pushed the fluid from the bleeder screws at the calibers and pushed the air out up through the lines to the master cylinders. Attached a rubber hose to the breather at the master cylinders and put the hose in a container so I could see when the system was bled. Took one try and and it was done.

I am pretty sure you can do the same thing purging air out of a hydraulic clutch.

This is the plane I was working on, not my own. It is hard to push the air down and out and easier to push the air up and out through the MC.