If you’ve just bought a new mattress and aren’t satisfied, don’t start the return process just yet. It might take a few weeks to fully “break-in” your new bed, and in the interim, it may not feel as soft and supportive as you’d like. This is especially likely if it came packed tightly in a box.After opening the box to air out the mattress, we recommend rolling or walking on its surface to even out the interior. Even then, it may take 30 days or more before the mattress fully settles into its final shape.;