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