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)(13,14,17,22,18,21,16,20)(15,19,24,26,23,27,25,28)(2,3)(5,6)(7,11)(8,10)(9,12)(13,15)(14,19)(16,25)(17,24)(18,23)(20,28)(21,27)(22,26) involution — undirected(5,7,8,12)(6,9,10,11)(14,20)(15,23)(16,17)(19,26)(21,22)(27,28)(1,3,4,2)(7,12)(9,11)(13,16,18,17)(14,20,21,22)(15,24,23,25)(19,26,27,28)(6,10)(9,11)(14,21)(19,27)(20,22)(26,28) 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.