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