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