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