Medal of Honor/Sneak Into Railstation

You'll be wearing a stolen captain's uniform during this mission, in an attempt to destroy a rail gun Greta.

As a stealth mission, there are only a few german soldiers around. It is also a short mission.

Switch Tracks / Obtain Ausweis Blau "Id Blue"
From the start, take a left turn, and climb the ladder found to the left of the locked door. This leads to a car storage, which will have a German officer at the end. Show the identification to this officer. Move behind him, and kill him with the silenced pistol.

You can collect the identification paper from the officer, and use the switch that the officer was overlooking, completing two objectives at once.

Backtrack to the starting area.

Obtain Ausweis Rot "Id Red"
Ahead of the starting area is one officer guarding a door. Show him the blue identification to get through.

Continue straight, and look for an air vent to the left of the door. Crawl through to the other side. You will have to shoot the vent cover, then quickly shoot the officer. Collect the identification card from the officer.

Level exit
Exit the room, and proceed through the next doors by showing your new identification.

The exit will be found on the right of the train, although there's a few more soldiers that will ask for your identification.