I really needed a new work skirt but as usual was struggling to find anything I liked or fitted me properly. So I bought some black fabric from the remnant bin for £3, and some cute anchor buttons 39p each so £2.34 for the 6 I bought. I found a really useful tutorial for a pleated skirt with a great formula to help you work out how much fabric you need for a pleated skirt. Unfortunately I could not find my tape measure. So I ignored the formula and just eyeballed some pleats in my rectangle of black fabric. 
It worked out fine. After I pleated I tacked along the pleats, then folded some black fabric to make the waist band and sewed that on the top of the skirt (which at this point still looked like a rectangle). I hemmed the edges of the fabric and sewed the buttons along the center edge, and button holes along the other. I HATE button holes, and they look entirely crummy. I hemmed the bottom of the skirt, and I was done.
