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