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