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