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