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)(11,15)(12,20)(13,21)(14,16)(17,18)(19,24)(22,23)(25,26,28,31)(27,33,35,30)(29,32,37,40)(34,39,36,38)(2,5)(6,7)(9,11,14,19)(10,15,16,24)(12,17,21,23)(13,22,20,18)(25,27)(26,30)(28,35)(29,34)(31,33)(32,38)(36,37)(39,40)(9,12,20,10,14,21,13,16)(11,17,22,24,19,23,18,15)(27,34)(29,37)(30,38)(32,40)(33,39)(35,36)(1,3,4,8)(2,6,5,7)(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.