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