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