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