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