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