Have done a lot of this recently, so just to make crystal clear the method is as follows...
It`s a two man job(natch)
Invest in a bleed pipe with a one way valve on the end like this:
ONE MAN BRAKE AND CLUTCH BLEEDING KIT NV16 UNIVERSAL
Attach pipe to the clutch slave cylinder nipple and put the valve end into a jar/jug with enough clutch fluid to cover the end and stop air being sucked up
With the correct spanner open the nipple and get the assistant to sit in the car and slowly depress the clutch pedal. Get them to tell you when they have reached the bottom of the clutch pedal travel and at that point you must close the open nipple
Get the assistant to raise the pedal and once fully up , you open the nipple valve and get them to push the clutch pedal to the floor. Again they must tell you when they reach the bottom and you again shut the nipple valve and get them to pull the pedal back up
Repeat this procedure until clutch fluid fills the clear plastic hose connected to the nipple and the assistant can feel the clutch pressure returning or fully returned.
There should be no air bubbles visible in the pipe at this point, indicating that all is well and you can now finally close the nipple.
This whole process can take some time to achieve so be patient, you will get there
Make sure to keep an eye on the fluid level in the reservoir at all times and top it up to prevent air being drawn into the system