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