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