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