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