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