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