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