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