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