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