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