Enemies always react differently, so there’s an element of chance in every encounter. Just because a strategy didn’t work the first time, doesn’t mean it’s always destined to fail. And if after a few times you still don’t succeed, simply approaching your target from a different direction or using a different weapon can result in success.
During the load screens, you’re shown quotes from Murphy’s Law of Combat. One of these quotes is “If it’s stupid but it works, it’s not stupid.” Take that to heart. It doesn’t matter how you accomplish your objective, as long as you accomplish it. Even if it takes all of your ammunition, get it done and move on. There’s plenty more to be found.
If you’re being overwhelmed by enemies, sometimes it’s a good idea to move right through them. You don’t always have to kill everyone. This is especially true on missions with a time limit. Always keep moving.
Possibly the most important tip for Modern Warfare 2 is to use common sense. If you’re impatient like me, you’ll want to sprint a lot. However, doing so requires you to stand up, which will often make you an easy target. If you have to cross a field while crouched or prone, it’s going to take a while, but you’ll have to deal with it.
Another common sense tip: semi-automatic fire is much easier to control than full on auto. Even if you have an automatic weapon, fire in bursts, especially if the target is a good distance away. If you’re trapped in close quarters with little chance of missing your target, feel free to spray and pray. Otherwise, it’s never a good idea.
You will come across things in the game that are exploitable, like spawn points. Use them to your advantage. Don’t feel dirty. Remember what I said about doing anything to win? War is hell, soldier. Do what it takes to win.
Article from Gamersyndrome.com