A method for applying a heat shrinkable film to a carton for forming a shape of the carton is provided. The carton includes a top panel, a bottom panel, at least one side panel extending between the top panel and the bottom panel, and a movable section that is movable between a first position and a second position. The method includes providing a heat-shrinkable but unshrunken film, wrapping the film in an unheated condition around at least a portion of the carton including at least a portion of the movable section of the carton, and moving the movable section from the first position to the second position to form a shape of the carton by heating the heat-shrinkable film to shrink the heat-shrinkable film into contact with at least a portion of the movable section.