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