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