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