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