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