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