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