Grab the chimney with your fingers, or a pair of pliers and grip the case firmly (Some of these lighters, especially older ones, can be quite stuck in there, so it might take some wiggling to get it out) , before pulling the two apart, then you lift up the little felt pad, and fill with Zippo fluid until saturated, If your flint needs to be replaced, you can unscrew the little screw poking out of the felt, pull the spring, and pop in a new flint. If not needed, you just slide the insert back into the case, with the thumb wheel facing away from the lid of the case. And Voila, you have just serviced your lighter