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