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