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