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