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