B flash out of apartments

Run forward (hold W), and as you move, jump-throw: hold left click, then jump and let go at the same moment.

From B apartments. Stand in the middle of the apartments hallway. Aim at the window grille on the far wall.

Practice (with sv_cheats 1): setpos -396.25 598.04 -80.29;setang -14.66 -175.52 0