Buy a good quality internal retaining ring set of pliers - preferrably with 45 and/or 90 degree tips. With engine off and cool, release pressure on the fuel rail by covering the schrader valve with a cloth and pushing the center of the valve (looks like a bicycle valve) until no more fuel runs out.

Take the pliers and squeeze the clip while lifting. Put lots of rags around the regulator to catch ring if it gets loose (which it can) then reomve the old one and replace with the new. Pay strict attention to part order. Instructions are also in the workshop cd you can download from my site or send a me an email with your address and I drop one in the post to you.