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