As soon as the mission begins, run forward until you see the crosses or are about four or five seconds in. Go to the right side against the fence and go prone. This must be done fast so the guards do not see that you are advancing toward your beginning position. Remain prone until four guards pass by. Crawl to a better position to view the advancing guards if desired. You can get up and continue to the right after the fourth guard passes, but stay along the fence. Then, run and go under a pipeline. Ignore the few guards to the left. Move slowly and continue to the right to eventually encounter a guard and a dog that will come up the path to the left. If you run, then you will not see the guard. There is another path to the left with two guards on the far side of it. Ignore this path and continue a few more steps to get beside a tree in the middle of your current path. From this tree position you can snipe those two guards. Before rushing onward, make sure to take out the guard and his dog in a small clearing to the left. You must advance slightly along the fence for a clear shot. Once that is taken care of, you can now continue past the two guards you just killed. Go prone a few steps ahead of them. There will be a small clearing and a patrol consisting of three guards and two dogs will pass by. Slowly follow after the last guard, making sure you keep your distance or else risk them seeing you. After a short distance down the path there will be one guard and a dog stopped just past the pipeline, but on the path. Wait for them to leave before continuing. After a few more steps, go prone and wait for another guard and his dog to leave as well, but stay close to the pipeline. There will be a guard walking to your left as well going toward where you came from. Once those guards leave the area, crouch down and sneak up the bank of snow and go underneath the large pipeline. Once you move ahead enough following the pipeline, you should see two guards at the top of the hill in front of you, just after the pipeline turns to your right. Snipe them quickly and move up the hill to their position. Once on top of this hill, you will see your green smoke and can quickly slide down the other side to complete the mission.