Have you seen this fun ruffle fabric? I have made TONS of stuff out of it. It's so cool and because the fabric is already ruffled it's super simple.
I Needed to make some new skirts for my 4 year old because she is growing like a weed. I simply measured her waist and cut a piece of the thick elastic just 1 inch smaller then her waist measurements. Then sew the elastic together so you have a circle. Next I measured from her waist to the middle of her knees and cut a large rectangle. I then pinned all the way down the side, (make sure that you pin it with all the ruffles pointing down so it lays right). You end up with a big tube.
Next I sewed a basting stitch along the top of the skirt and pulled it so it ruffled. I ruffled it until it was the same size as the elastic that I cut earlier. Then pin the elastic and the skirt together. Next just sew the elastic on and your done! It doesn't need to be hemmed or anything.
SO simple yet so cute. Trying to take a picture of her in the skirt is a lot harder then actually making the skirt. I couldn't get her to hold still and these pictures are the best I could get.