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