[dpvu]

Just take the slide off every once in a while and clean it all out. Once it's all clean, re-grease all the moving parts with light silicone oil or white lithium grease (some don't like this stuff because it's white and it may or may not damage the seals so don't use it in mags). Put it all back together and make sure your slide moves freely and you should be good to go. It's usually not necessary to take the little bits apart (trigger assembly, hammer assembly etc.).

You also need to take care of your mags so they don't break or leak. Always keep some gas in there. It doesn't have to be full but there needs to be some in there so the seals don't dry out. Also lubricating the seals occasionally by putting a couple drops of light silicone oil on the gas release valve and working it inside and also on the fill valve and working it inside with the propane adapter (when unconnected to the tank) once in a while is a good idea.