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