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