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