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