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