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