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