On top of the foam board frames, I sculpted the shapes using crumpled newsprint paper and masking tape. After which I did a mâché layer with paper towels and a flour-based paste.
Following that, I smoothed things out with another mâché layer, this time using newsprint and a watered-down white glue paste.
Finally, I added tongues and teeth... which they sell on amazon for some reason. Thank you god-king Bezos, now go fly your dick rocket into the sun.