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