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