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