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