On some maps there are specific location that your enemies tend to go to. This only works if you are playing a public match on multi-player online.
Ambush
You can plant claymores in the entrances to the underground tunnel. Also, look for snipers up on rooftops and enemies just running through the map.
Backlot
There is a building with the turret that has a large staircase (and a big hole on the second floor walls). This building is at a corner of the map. It is across the street from the two-story building with an accessible roof (the one with a garage and a car in it).
Chinatown (Map Pack)
There is a two-story building with two rooms on the second floor. One staircase leads up to these rooms. In one room there is a fridge and a couch by a window. This building is often used by enemies to get away or run through. Hide or crouch beside the fridge and you may be able to kill some enemies without them noticing you, because enemies are often too busy running through or sniping.
Countdown
At the sides of the map.
Crash
Enemies that prefer sniping will go to the building opposite from the blue building (the one with a "balcony" and a ladder leading to the balcony). The blue building (with an almost-wrecked staircase and blue interior) is also a good location to plant claymores because enemies and teammates often fight over that building. Also, the building facing the back of the crashed helicopter tends to attract enemies.
Creek (Map Pack)
Do not bother guarding or hiding in the creek. Barely any enemies go in there. Instead, sneak over to the area with the waterfall. You can also find enemy snipers and "teammate-pursuers" up on the narrow mountain with the sand bags at the top. This mountain is attached to the cave. It also has a trail going across the side of it. To get to this mountain, go to the side of the map with the barn house and the other wooden buildings. Then, go up the short, steep trail that leads to the top.
Overgrown
Enemies tend to run around and snipe in the other side of the map (with the barn house and the building with an attic).
Shipment
The corners of the map are sometimes filled with easy-target enemies.
Wet Works
Often enemies run around and shoot people at the sides of the ship. Throwing a grenade there often weakens or kills an enemy, if present.
