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