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