Depends partly on what pipes your are using- if using solid cast pipes then you'll need a female to female adapter and then just thread the end of the pipe. If using hydraulic flexible pipes then its just a matter of crimping an M25 thread connector on the end of the pipe. You could also just get the right size pipe with the right thread on the end to screw into the inner thread on the valve (1/8 bsp) and then jut connect that to the rest of your 1/2" pipe work via a T connector with the right sized ports.
So basically it depends on the rest of your pipe work.