[knowledgeORbust]

If you've never really played FPS games before, and want to work on your raw killing skills, you should probably play Lone Wolf. It will put you in lots of tough situations and force you to get competent at killing and survival. But team games are where the real strategy is at and will force you to think on top of improving your instinctual-type skills. Whatever you play, you should probably make it ranked.

The #1 thing to concentrate on for any player is awareness. You can only be so good at handling the weapons that the game inevitably comes down to awareness at mid-higher levels. I like to learn weapon placement, map-layout, and other little tricks as I go along. If you're 100% completely lost, try running around an empty map and looking around or, better yet, following around a teammate - that way you can learn the map and other players' strategies at the same time.

Once you've got the general flow of games down and know the map a little bit, you should start thinking "what should I be doing right now?" Each player is a part of an organism, the team, and you should, on top of whatever's going on on your screen, also have another train of thought running through your mind illustrating each whole organism. You want to know where everyone on your team is, where everyone on the other team is, what each is doing, and then where you best fit in at that time.

Awareness is key and it comes through tons of play. Play, think, and watch what everyone is doing. If you can communicate while you do that, that's a whole other skill that tons of players lack. Simple stuff like "there's a guy at <general location>" is always good. Throughout a game there should rarely be total silence.