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