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)(13,14,18,19,17,22,15,23)(16,26,24,28,27,21,25,20)(1,2)(3,4)(5,6)(7,11)(8,10)(9,12)(13,15,17,18)(14,19,22,23)(16,25,27,24)(20,26,28,21)(5,7,8,12)(6,9,10,11)(13,16,17,27)(14,20,22,28)(15,24,18,25)(19,21,23,26)(2,4)(7,12)(9,11)(13,16)(14,21)(15,25)(17,27)(18,24)(19,20)(22,26)(23,28) involution — undirected(6,10)(9,11)(13,15,17,18)(14,19,22,23)(16,24,27,25)(20,21,28,26)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.