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