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