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