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)(13,14,17,22,18,21,28,24)(15,23,25,16,20,19,26,27)(5,6)(7,11)(8,10)(9,12)(13,14)(15,23)(16,26)(17,24)(18,21)(19,20)(22,28)(25,27) involution — undirected(2,4)(5,7)(6,9)(8,12)(10,11)(13,15)(14,19)(16,24)(17,25)(18,20)(21,23)(22,27)(26,28) involution — undirected(7,12)(9,11)(13,16,17,19,18,27,28,23)(14,20,22,26,21,15,24,25)(6,10)(9,11)(14,21)(15,20)(22,24)(25,26) 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.