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