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