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