How do people get good at call of duty?
Been hovering around 0.5-0.7 for TWO YEARS and I still haven't seen any noticeable improvement.
Use sound more. Footsteps changing between surfaces, knees cracking from large drops, suppressed guns firing, your teammates' groans as they die all provide useful information. You should never die to stealth bombers. A good stereo or surround headset and SitRep Pro will let you reign over the idiot masses.
Look at the minimap. No, look at it more than you already do. But beware:
People over-rely on the minimap and being "invisible" is a huge advantage -- use Assassin and a silenced weapon. The ACR is a great option.
Sometimes I'll get a few shots on someone as they're going around a corner, and they survive, but then they make one of two choices: 1) Desperate for someone to shoot, they run back around the corner to try to shoot me. This person usually has no idea where I am, and I know exactly where they're coming from, and I'm already aiming down my sights, and they're already badly hurt. This choice almost always gets them killed. Or 2) They don't run back around the corner, forcing me to either let them go, or chase them, giving them the upper hand to hide wherever they want, waiting for me to come around the corner. Don't be like the first group of people.
Somewhat related to the above, don't shoot at something you can't kill, even with a silenced weapon. Giving away your position is a bad idea.
Stay away from your teammates. If you're playing in public lobbies, they're all morons who will only get you killed.
When enemy air support is up, either don't go outside, or shoot it down with Blind Eye. Don't be like the idiots who run around oblivious to what's going on in the game. I can't believe helicopters ever get kills, but they do.
So many people play these games that a little bit of not-being-stupid goes a long way.