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