Go up the steps then turn left and go up the stairs. Go up five steps then wait near the windows on the right.
At the top of the stairwell, enter the white double doors. Upon entering the doors, veer to your left towards the staircase in the room. Proceed up the steps to the first landing on the stairwell.
Continue up the stairs into the room. Go up some of the stairs on the left and stop infront of the open window.