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