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