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