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