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