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