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