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)(11,14)(12,15)(13,17)(16,20)(18,22)(19,21)(23,24)(25,26,29,31)(27,35,37,40)(28,34,30,33)(32,36,39,38)(1,3,5,4)(2,6,8,7)(9,11,13,18)(10,14,17,22)(12,19,20,24)(15,21,16,23)(26,31)(27,36)(28,30)(32,35)(37,38)(39,40)(10,15)(12,20)(14,21)(16,17)(19,24)(22,23)(25,27,29,37)(26,32,31,39)(28,36,30,38)(33,40,34,35)(1,4,5,3)(2,7,8,6)(11,18)(14,22)(19,24)(21,23)(25,28,29,30)(26,33,31,34)(27,36,37,38)(32,40,39,35)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.