How would I gather a skirt like this?

a href="http://c.shld.net/rpx/i/s/pi/mp/3883/2148813101p?src=http%3A%2F%2Fsite.pacificplex.com%2FSears%2Fsrs-gl-14350.main.jpg&d=933218692cabb3bf97ce1ca01d8d17efaca0eb31&hei=248&wid=248&op_sharpen=1&resMode=sharp&op_usm=0.9,0.5,0,0" rel="nofollow"http://c.shld.net/rpx/i/s/pi/mp/3883/214…/a