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