You begin facing a wall, you're standing on a staircase, looking slightly to the right, take 2 steps to go down the staircase and you will go through the archway on the left, when you are standing in the archway, you see a room with 3 bookshelves, 2 to the left, 1 in the very far corner in the right, take a step towards the bookshelf that's in the very far corner to the right and you're done.