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