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)(11,15)(12,14)(13,16)(17,18,21,19)(20,23,24,22)(25,26)(27,33)(28,36)(29,30)(31,35)(32,37)(34,39)(38,40)(1,2,4,6)(3,5,8,7)(9,11,14,13)(10,15,12,16)(17,19,21,18)(20,23,24,22)(26,30)(28,37)(31,33)(34,38)(1,2)(3,5)(4,6)(7,8)(9,11,14,13)(10,16,12,15)(25,26)(27,33)(28,32)(29,30)(31,35)(34,40)(36,37)(38,39)(1,2)(3,5)(4,6)(7,8)(9,12,14,10)(11,15,13,16)(17,20,21,24)(18,22,19,23)(25,27,29,35)(26,31,30,33)(28,38,37,34)(32,40,36,39)(1,3)(2,5)(4,8)(6,7)(9,13,14,11)(10,15,12,16)(25,28)(26,32)(27,34)(29,37)(30,36)(31,39)(33,40)(35,38)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.