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