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