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