You begin facing into a tan hallway. Go ahead and step forward through it. Keep going through the glass doorway until you hit the top of the staircase. You don't want to go down the staircase, instead head left, into the entrance of a hallway you can see there. You'll likely step into the entrance of the walk-in closet, but you want to go further past that, in to the bathroom. Once you have entered the bathroom door, you're done.