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