first of all u got to close the brake fluid circuit.
after that u get a transparent tube and connect it with the caliper.
a tool to undo the screw also so u can open and close it.
You refill the brake fluid chamber and pull the brake lever.the screw at the caliper needs to be open.(brake fluid and the bubbles are getting out)while u pulling the lever,u got to close the screw at the caliper AGAIN without leaving the brake lever back.you keep doing this for MANY times.the outcoming brake fluid in the tube,put it vertical so it doesnt catch wrong air.it takes quiet some time...once its done,no bubble should come out anymore.close the circuit and pull the lever several times.it should gain on pressure...remember of course,while pulling that there is ENOUGH liquid in the chamber so it doesnt suck false air while u releasing the air at the bottom