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