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