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