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