Off CT spawn, go to where the fence to long and the front of the APC meet. Slide into that grove. it should funnel you into the spot if you do it right. Next turn around and face A site and look for the vents on the structure to the right of the crashed truck. There are 3 sections with 2 dividers. Line your corsshair up with the divider between the leftmost vent and the middle vent; anywhere on that bar is fine. Then jumpthrow the smoke. It should land perfectly in the tube and obscure any lines of sight through it.