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