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