This is a different paper popper, and can still be made with a rectangle. both models can be made with a rectangular sheet of newspaper for a louder bang. or in this case, a crack!!!
this popper makes a sound like a cracking wip.
Step 1: 1
fold on the dark line through the middle
Step 2: 2
fold the two corners down on each side, with the last fold from step 1 on the bottom. btw, the gray represents the other side of the paper.
Step 4: 4
fold on each side along the lines, middle fold first. the middle fold should be a mountain fold, and the other two shold be valley folds. flip over to get it oriented right for the next picture.
Step 5: 5
eek, forgot about the end... sorry. here it is.