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