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