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