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