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