Take it apart, examine the pieces parts, marvel at the design, drool a bit, clean the shite that looks sticky, icky or otherwise might cause me heartache and lube it properly! Reassemble, marvel at the design, drool a bit more and go blast away at something.
My BIL's PPK was really nasty when he bought it and it wouldn't fire consistently. I figured he at least lubed the thing but alas, he's a dumbass. He gave it to me for a couple of weeks and like Frank said, it was really icky, sticky! After some proper love, it's 100%!