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)(19,25)(22,31)(26,32)(27,30)(2,5)(6,8)(9,11,13,12)(10,14,15,16)(17,18)(19,26)(20,24)(21,29)(22,27)(23,28)(25,32)(30,31)(9,12,13,11)(10,14,15,16)(17,19)(18,22)(20,25)(21,30)(23,32)(24,31)(26,29)(27,28)(18,23)(21,28)(22,32)(24,29)(26,31)(27,30) involution — undirected(1,3,4,7)(2,6,5,8)(19,25)(22,31)(26,32)(27,30)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.