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