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