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