One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10,12,14)(11,13,15,16)(17,18)(19,26)(20,28,29,31)(21,25)(22,23)(24,27,32,30)(2,5)(3,7)(9,11)(10,13)(12,15)(14,16)(17,19,21,22)(18,23,25,26)(20,27,29,30)(24,31,32,28)(11,15)(13,16)(17,20)(18,24)(19,27)(21,29)(22,30)(23,31)(25,32)(26,28) involution — undirected(1,3,4,7)(2,6,5,8)(19,22)(23,26)(27,30)(28,31)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.