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