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