I used white duct tape because it is easier to draw on. Try to not use gray duct like (aka the "real" duct tape) because its stickier and harder to work with. The colored duct tape is so much easier to cut and relatively cheap to buy. I got mine at the drug store around the corner but you can also find them in any craft store. Go crazy with the color!
Cut out the printer paper into a smaller 8 inch by 6 1/2 inch rectangle. Place the longer side on the top of the page so the paper is longer vertically.
Cut out strips of duct tape so they are slightly longer than the page on the right side. Place them vertically on the paper making sure to cover the side entirely while overlapping the pieces.
Flip over the paper repeat the WHOLE process.
Make sure to NOT cover up the small strip that is sticking out on the left side.
Fold paper vertically, as if you were making a tube and make sure the line of duct tape sticks to each other.
Be very careful. Put the "seam" of the duct tape in the CENTER of the tube. If you put it to the side it doesn't look as good and is more difficult to cover up.
Tuck in one end of the tube just like if you were to wrap a present. Use tape on the outside and the inside of the tube to hold down the end.
Pull a long piece of tape and wrap it around the "seam". Don't cut until you made it all the way around. This gives it a really cool pin stripe sort of thing and hides the "seam" really well.
Cut into the side about an inch or so. Continue and cut out a rectangle on one side only. This should also leave a rectangle on the side still attached.
To make it pretty fold the sides of that rectangle to make a triangle and hold it with a small piece of tape.
Now to make a pouch to tuck in the flap.
Cut out a piece of tape long enough to circle the case. Then place the rectangle you just cut out in the center of the tape touching the top of the strip.
Try to place the rectangle attached to the strip directly in front of your triangular flap. Once you have it right wrap the rest of the strip around the case.
Congratulations! Now you're done with the construction. Pimp out your case or rock a solid bold color. :)