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