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