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