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