Pam it. I use Pam cooking spray. I drilled 3 holes in the bottom, at 12 oclock, 4 oclock, and 8 oclock. Drill about 3/8" diameter holes. flip the bucket over, and put a 1" square of duct tape over the 3 holes, then spray Pam on the inside. Then pour your concrete. After it sets up, flip it over, and using the 3 holes, push the concrete out using the 3 holes. There is enough taper in the bucket that it will come out easily once you get it started. I have been using the same 2 buckets for forms for several years to make anchors/weights. A little harder to make boo buckets, but it still works. You just turn it on its side, and get buddy to help pull it out of the bucket