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