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