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