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