What is the best stealth smoking technique for my situation?

[Sinsemilla]

roll a joint and stick your head out the window and above the opening, sit on the ledge if you can, just dont fall

thats wat i do.
except the sitting part.

one time i leaned out my window, and saw a cop car just sitting there in the middle of the street, i froze, i was like "oh sh*t im busted", but after a minute he left.