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