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