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