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