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)(11,15)(12,16)(13,21)(14,18)(17,22)(19,24)(20,23)(25,26,29,32)(27,33,35,30)(28,31,37,40)(34,39,36,38)(3,7)(5,8)(9,11,14,12)(10,15,18,16)(13,19,22,20)(17,23,21,24)(25,27,29,35)(26,30,32,33)(28,36,37,34)(31,39,40,38)(1,2)(3,5)(4,6)(7,8)(9,10,14,18)(11,16,12,15)(13,21,22,17)(19,23,20,24)(25,27)(26,30)(28,34)(29,35)(31,38)(32,33)(36,37)(39,40)(9,12,14,11)(10,16,18,15)(13,20,22,19)(17,24,21,23)(25,26)(27,30)(28,31)(29,32)(33,35)(34,38)(36,39)(37,40)(1,3)(2,5)(4,7)(6,8)(9,10)(11,16)(12,15)(13,17)(14,18)(19,24)(20,23)(21,22)(25,28,29,37)(26,31,32,40)(27,34,35,36)(30,38,33,39)(1,2)(3,5)(4,6)(7,8)(9,13,14,22)(10,17,18,21)(11,19,12,20)(15,23,16,24)(25,26)(27,30)(28,31)(29,32)(33,35)(34,38)(36,39)(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.