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