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