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