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