shit man, last summer i would smoke in my rooom every day literally and not once did i get caught...but one time i smoked like 9 bowls with my friend and my mom thoguth i was smokin cigs the next morning lol...but all u gotta do is put a towel at the door open the window as much as it will go and try to keep ur head outside the window everytime u take a hit, light an incensee stick and put the window down to about a 1/3 of the way closed so it'll create a suction and filter out the air from the room...thats pretty much it..always have some gum handy and some axe just incase they knock on the door, prolly wont happen tho, happy toking