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