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