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