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