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