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