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