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