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