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