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