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