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