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