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