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