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