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