Cover is your friend. Unless an enemy is actively shooting at you or moving directly toward you, cover keeps you from notice, and if you aren’t detected, it leaves you free to pursue your tactics without enemy interference.
When you leave cover, you should always have the next cover spot in mind. If enemies patrol the area, try to wait until they are out of sight, have their backs turned, or are at the farthest point from you on their patrol route when you leave the safety of your cover position.
Firing from cover is a good idea if you can stay hidden and still pick off enemy targets. Drop prone if you can to steady your aim and stay concealed. Unfortunately, your shots will usually draw attention to your position, and you should be moving to your next cover spot before the enemy turns up the heat on you.
Remember, don’t expose yourself to unnecessary fire. A frequent mistake by beginners is to charge into a new area to see what’s there.
Granted, if you’re willing to restart the mission over and over, you can learn the lay of the land that way, but it’ll be painful. A safer course might be a plan like this: While entering an area, rounding corners and descending hills, you always want your gun facing the new area. By hugging building walls and trees with your back, you gain cover and maintain position on your eventual enemies.
Visibility Indicator
This indicator shows the enemy’s field of vision in the area and the likelihood that you will be spotted in your current position. If an enemy looks in your direction and you’re not hidden, the indicator begins to tick and the indicator’s red ring will begin to expand. If the ring expands into a full circle, the enemy has spotted you, the alert goes up, and the enemy will fire upon you if he has a shot.
The arrow on the ring marks the enemy’s direction, so check the arrow for the enemy position and react accordingly. Unless you need to move quickly out of an enemy swarm, you generally want to drop prone or seek immediate cover as soon as you hear or see the Visibility Indicator activate. Continue to slide into cover and put an obstacle between you and the enemy to avoid detection.