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