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