Here are some tips:
Start= I usually take the right path right at the start of the map and kill terrorists from there. You will be able to kill terrorists in the area near the big bus, as well as those that are behind the river, near the wooden sheds. Your teammates might want to advance from the front and left of the bus area, to surround them all. Once this section is clear, proceed to the river and get to the far end where a gap in the fence lets you reach the second section of the level. You can kill a lot of terrorists before entering the docks by staying on the opposite side of the river and shooting from afar.
Docks= As soon as you get in, turn left, there is 1-2 guys there that are right in your face. Take them out and proceed (any way you want) through the docks. Watch out for a turret-mounted truck that will arrive once you progress through the area. You will have to reach the western part of the docks to blow up tanks. The explosion will bring fresh forces to your location, so watch out and plan your escape. From there, you also see far ahead and you can take out terrorists in the distance (e.g., on the piers).
Boats=Further north, you will come to a wall where stairs go up or down. Terrorists often pop from the basement, so I usually take them out and go downstairs. Have friends take the upper route so they protect you while you rig the boats. If you take the upper route, make use of the long-range sight that you have in this section and take out enemies from afar (you can't rig the boats if you go there, so someone must go through the basement).
Data= Now go to the top-right (or North-East) of the facility, where the containers are stacked, and progress slowly. Once you kill everyone, retrieve the data. This is not too though, so if you're in a big team, 1-2 players can take care of it while others clear the upcoming section for extraction.
Extraction= Look out for the armored truck! It will get you from behind if you don't take care. I usually like to take cover in the brown hangar (between data and extraction, with containers and no walls), because from there I can take out soldiers running between the vans, and I can see the truck most of the time. Once you blow it up, proceed to the lighthouse, but watch out for enemies directly at your right when you cross the big fence.
Good luck. It's doable with 2 players, but it's pretty rough ;)