1: Lift board up on your left then open top drawer. 2: Put the key in the keyhole on your right. 3: Pull lever down (keep broken handle) and keep pulling rope down until you can't anymore. 4: Use the yellow level in-front of you to pull up the clock. 5: Take the broken handle from before and put it in the crossbow on your left. 6: Put the code "2112" into the box behind you on your left the take the canister and hover it in-front on you until needed. 7: Put the light setting onto the chair option. 8: Wait for the mask to lower then either take the gas out of the back and put the canister into it or put it in the masks mouth. 9: When the first operative is blinded on the balcony spam the top-right sound button until the door closes on the second operative beneath you. 10: Take the crossbow with the handle loaded into it and shoot the operative on your left.

Then that should be the end of the level. this is also from memory so forgive me if anything is off