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