Not that ruffles themselves aren't
great, but let's actually put these ruffles on
something. Go back to the shirt you turned into a tank
top, er... purse.
Snip it up the sides, along both seams.
Then, open it up (it should flap open at the tops of
your "handles") with the front of the shirt facing up.
We want it facing this way so we can mock up our ruffles