i use good old fashinoed boot polish, little round tin, good cotton rag, and a buffing brush.
get a lighter, light up the boot polish(turns it liquid pretty quickly) cover the top to put the flames out, then start applying, does take time, and you will probs wanna give the bumper an application with a brush then a cloth, and if your really anal like me, then youll mask up all the painwork thats close to the trip to avoid getting black on it(major pain with a white car!)
once its all rubbed in(2 coats does me fine) then get the buffing brush, and buff away, gives it a nice(but not over the top) shine, and last for fooking ages! plus makes the water bead like mad and looks cool!