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