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