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