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