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