Found on Pinterest.
Only problem was that every time I tried to pull a string to create the ruffle the little string broke because my material wasn't good enough. Then I realized you actually have to sew a line down the centre first with a strong piece of string and then pull.
Here's a more detailed run-down of how I made my ruffles:
Cut a 17" piece of material and then realized I didn't know how to divide it evenly into the right number of pieces so I just folded it until it looked about right.
Then cut the curves to get something that looks like below.
About 12 evenly spaced lines. Which I tore into strips:
What do you think? Think it will make a cute mustard colour pillow?