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