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