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