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