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