A good tip is don't try to play Battlefield 3 like COD. If guys on your team are set up, don't try to rush in to the blind spots. Look for destructible walls and entrances that can lead to alternative routes instead of walking towards enemy fire.
Using back, select or the q button, depending on what platform you are playing on will allow you to see enemy players from long distances or when they blend in with the background. There will be a triangle that hovers directly over their head, now you can aim and shoot at them better. This will help with your overall total of kill shots.
Make sure to drop a health pack at your feet, so when you engage in a gun fight and take damage from shots, the health pack can bring your health levels up. This is effective when hunkering down and shooting at the oncoming enemy.
Take a minute out of your play to check inventory in a safe place, you earned it, so make sure you utilize it before you move on to the next area of game play.
Whenever you revive someone, make sure you know what killed them, so it does not end up killing you too.
Get used to the gun because it will sway a little while shooting and make aiming at targets harder. The guns have a lot of recoil, so you should probably turn off vibration on your controller because it is not needed. If however you must have vibration on, try to hold the controller in way that allows for the gun to shoot as accurate as possible.
If you want to know in-depth strategies that the pros use, then checkout out this game guide packed with everything you need to succeed and climb up your team's ladder quicker than ever!
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