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