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