Method and apparatus to agitate a liquid are disclosed herein. An example apparatus includes a carrier having a base that includes a ridge extending from the base and a collar extending from the base. The example apparatus also includes a container supported on the base, the container movable between (A) a locked positon in which the ridge fixedly engages the container to non-rotatably couple the container to the base and (B) an unlocked position in which the container is disengaged from the ridge and the container is rotatable about the collar.