The present invention provides causing a plurality of filling chambers to be opened and mixing agents inside the filling chambers using users general operation between taking out a packed multi-chamber container and mounting the container on a device. The users general operation includes operations for taking out a packed multi-chamber container and removing the package, for unfolding the multi-chamber container typically folded in two, for mounting i.e. hanging the unfolded multi-chamber container on the device, and the like.
