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