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