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