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