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