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