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