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