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