You will start by standing on the staircase to your left. Continue to walk up the staircase. There will be the first landing where there's another staircase on your left and another one on your right. Continue to go inside the room in front of you which is a wine cellar. Now turn left in this room and jump over the two stools towards the other side of the room. Now turn right once again and take one step towards the corner of the room. Turn around and face the opening to this room and you will see the staircase from here. Jump over this table and the stools towards the stairs outside. Once you're facing the brown door in front of you and the other set of staircase on your right then you're done.