It's pretty simple, really. You have a paintball gun, you like to shoot people, and you don't wanna mess around with a poorly functioning gun.
So get some Spot marker oil, and all you need to do is put a few drops of this magic elixir on your moving parts (bolt and striker, mainly) every week or so. It might help if you clean the parts off first, but hey, who's keeping track? Spot oil is longer-lasting and doesn't break down quite as easily as the cheap versions do.
Buy a pack of 12, sell it to your friends, and you might even get your own bottle for free!