Turn mat on and place on top of crib mattress. (tranquilomat.com)
The Lifenest fits securely on top of your crib mattress and has a mesh insert where the baby rests which has some give to it, and therefore does not put any pressure on a single spot of the baby's head, but actually cradles it. (babyflathead.org)
My wife used her MacGyver skills and wrapped some towels around the top of the crib so the little guy wouldn't crack his brand new teeth on the cage, er I mean crib. (havebabywilltravel.com)