You need,some fabric (a hard one preferably. I used neoprene with black on one side and grey on the other. 2 for 1! yaay), a pair of scissors, a blade, a maker pen, measuring tape and/or ruler, a zip and some pins.
First, draw some patterns onto your fabric with the marker pen. It can be any pattern you like. I did geometric shapes.
Once you've filled the whole piece with the patterns, start cutting using the blade or scissors.
When that's done, its time to inserts the zip. Sew one side of the zip to the short piece of fabric and the other side to the longer piece. Once this is done, zip the zip together and cut off any excess.
Unzip the zip and sew the edges of the plain bits of fabric together (remember to sew them inside out because you gotta turn them out) then turn right side.