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