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