Get a bleeding kit from a local accessory shop. Start off on the furthest from the master cylinder, undo the bleed nipple plug on the hose from the kit, other end in a jar or summit, pump brake pedal at least 6 times. tighten bleed nipple then top up master cylinder and move onto the next furthest away. Repeat process till all four done. Nothing difficult about it. Dont forget to keep topping up master cylinder though.