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