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