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