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