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