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