If the clutch master cylinder is fed from the brake master cyinder resovoir, make sure the resovoir is filled up well above the clutch master cylinder feed pipe. To bleed it,you could try opening the bleed screw & allow it to bleed by gravity, or you may be able to use a pressure bleeder ,such as gunsons eazi bleed. Another option is to open the bleed screw & push the piston rod of the slave cylinder in,(if you can get to it) then tighten the bleed screw & release the piston,repeat this several times, this should pull fluid through by vacuum. Some hydraulic clutch systems also have a damper valve in the pipe which can cause problems, i often by pass these if i think they are causing a problem, they are often not needed.
jim
June 2010