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