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)(11,13,15,16)(19,23)(22,24)(26,31)(28,35)(33,37)(36,40)(2,3)(4,8)(18,21)(22,24)(25,26,30,31)(27,28,32,35)(29,37,38,33)(34,40,39,36)(2,3)(6,7)(17,18,20,21)(19,22,23,24)(25,27)(26,28)(29,34)(30,32)(31,35)(33,36)(37,40)(38,39)(1,3,5,2)(4,7,8,6)(9,10)(11,13)(12,14)(15,16)(25,28)(26,32)(27,31)(29,36)(30,35)(33,39)(34,37)(38,40)(1,4)(2,6)(3,7)(5,8)(9,11,12,15)(10,13,14,16)(17,19)(18,22)(20,23)(21,24)(25,29,30,38)(26,33,31,37)(27,34,32,39)(28,36,35,40)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.