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