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