This is the easiest way to make a gravity bong. (In my opinion) Step 1: Buy a 2 litter soda http://ibuybackcolorado.com/uploads/2/9/4/6/2946853/6184042_orig.jpg Step 2: Drink/Poor the soda out. Then, towards the bottom of the soda there is a ring going all the way around the Bottle. Cut all the way around it so the bottom 1/8th of the bottle is cut off http://www.weedmania.co.uk/images/h...ong/how-to-make-a-bucket-bong-cut-bottle1.jpg Step 3: Cut a hole in the middle of the lid by sticking a knife on it and twirling it around. Make sure the hole is the perfect size to put your bowl piece into so that it's air tight. Once done with that stick your bowl piece in and leave it. http://pothead.org/wp-content/uploads/2011/05/Gravity_bong_lid.jpg Step 4: Get a water jug, that the 2 liter bottle can slide in and out of easily. (Can get at Walmart) http://i00.i.aliimg.com/img/pb/485/218/214/1239868405802_hz_myalibaba_web11_1907.jpg (Something like that) Just throw the lid away. Step 5: Fill the Jug with water. After that, put the 2 liter in (without the cap on). Then, Screw the cap on so it's air tight. Step 6: Pack a bowl and get high Got all my pictures off of Google images. Sorry I couldn't make a vid/take pics my self as I currently do not have a camera. If you have any suggestions please add!