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