You know that scene in the Jurassic Park movie? Where there's this big dinosaur print, big enough to step into?
Imagine a footprint so big that you can stand in it without knowing it's a footprint, and you leave your own teeny tiny adorable little footprints inside it.
Not sure? They may have done that too, or instead. As far as that goes, I seem to remember it being done in land of the lost (the show, can't remember if it's in the movie or not).