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