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)(14,19)(15,24)(21,26)(22,23) involution — undirected(6,9)(10,12)(13,14)(15,25)(16,21)(17,19)(18,22)(20,26)(23,28)(24,27) involution — undirected(2,4)(13,15,17,24)(14,20,19,16)(18,21,28,26)(22,25,23,27)(5,7,8,11)(6,10,9,12)(13,16)(14,21)(15,22)(17,20)(18,25)(19,26)(23,24)(27,28)(14,22)(15,24)(16,25)(18,28)(19,23)(20,27) 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.