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