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