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