One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,7,8,5)(9,10,13,17,14,19,12,18)(11,20,21,15,23,24,22,16)(25,26,30,32,29,33,28,34)(27,35,36,31,38,40,37,39)(1,3,4,8)(2,5,6,7)(9,11)(10,15)(12,21)(13,22)(14,23)(16,19)(17,20)(18,24)(25,27,29,38)(26,31,33,39)(28,36,30,37)(32,35,34,40)(9,11)(10,16)(12,21)(13,22)(14,23)(15,19)(17,24)(18,20)(26,32)(27,36)(28,30)(33,34)(35,40)(37,38) involution — undirected(9,12,14,13)(10,17,19,18)(11,21,23,22)(15,20,16,24)(26,33)(31,39)(32,34)(35,40)A 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.