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