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