One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10,13,15)(11,14,12,16)(19,26)(22,31)(27,32)(28,30)(2,5)(6,8)(9,11,13,12)(10,14,15,16)(17,18)(19,27)(20,24)(21,23)(22,28)(25,29)(26,32)(30,31)(9,12,13,11)(10,14,15,16)(17,19)(18,22)(20,26)(21,30)(23,27)(24,31)(25,32)(28,29)(18,23)(21,29)(22,27)(24,25)(28,30)(31,32) involution — undirected(1,3,4,7)(2,6,5,8)(18,24)(19,26)(23,25)(28,30)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.