Most maps have certain locations that players always tend to go to on multiplayer games. The following is a list of maps followed by their popular locations:
Crash Players that prefer sniping usually 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 great location to plant claymores because players and teammates often fight over that building. Also, the building facing the back of the crashed helicopter tends to attract players.
Overgrown Players tend to run around and snipe on the other side of the map (with the barn house and the building with an attic).
Wet Works Often, players run around and shoot people at the sides of the ship. Throwing a grenade there often weakens or kills any enemy there.
Shipment The corners of the map are occasionally filled with easy-target players.
Backlot There is a building with a turret that has a large staircase (and a big hole on the second floor walls). This building is at one of the corners 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 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 usually used by players to get away or run through. Hide or crouch beside the fridge and you may be able to kill some players without them noticing you, because players are often too busy running through or sniping.
Creek Do not bother guarding or hiding in the creek since hardly any players 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.
Countdown Players like to go on the sides of the map.
Ambush Plant claymores in the entrances to the underground tunnel. Also, look for snipers up on rooftops and players just running through the map.