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