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