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