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