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)(13,14,19,22)(15,23,25,27)(16,21,18,17)(20,26,28,24)(5,6)(7,11)(8,10)(9,12)(13,15)(14,20)(16,24)(17,23)(18,26)(19,25)(21,27)(22,28) involution — undirected(2,4)(5,7,8,12)(6,9,10,11)(13,16,19,18)(14,17,22,21)(15,24,25,26)(20,23,28,27)(7,12)(9,11)(13,17)(14,16)(15,20)(18,22)(19,21)(23,26)(24,27)(25,28) involution — undirected(6,10)(9,11)(13,16,19,18)(14,21,22,17)(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.