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