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