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