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