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