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