Right now you're facing towards the open arch and move towards the open arch. Turn left and move forward. Turn slight left you'll see stairs, move towards the stairs and go down the stairs completely. Right now you're in entrance of a room and enter into the room. You'll see taps which are in your left, pass all the taps, turn slight left you'll see steps and stand on the first step. Now you're facing towards the white colored bathtub and that is your end point.