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