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