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