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