An apparatus and method are provided for mixing paint disposed in either a conventional one gallon paint container or a square paint container having a body with a handle passage extending therethrough. The apparatus includes a square bucket for holding the container. A rocker is pivotably mounted to a side wall of the bucket and includes a pair of heads aligned over a pair of openings in the side wall. A floor of the bucket has a plurality of support structures extending upwardly therefrom. When the conventional one gallon paint container is disposed in the bucket, the container rests on the floor, the vertical axis of the container is offset from the central axis of the bucket, and both heads of the rocker are disposed against the container inside the bucket. When the square paint container is disposed in the bucket, the container is supported on top of the support structures so as to be elevated above the floor, the vertical axis of the container is collinear with the central axis of the bucket, and one of the heads of the rocker is disposed in the handle passage of the container.