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