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