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