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