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