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