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)(11,17)(12,13)(14,22)(15,16)(18,23)(19,20)(21,24)(25,26,29,32)(27,33,35,30)(28,31,37,36)(34,39,40,38)(1,3,5,8)(2,6,7,4)(9,11,15,13)(10,12,16,17)(14,19,23,21)(18,20,22,24)(25,27)(26,30)(28,34)(29,35)(31,38)(32,33)(36,39)(37,40)(1,3)(2,4)(5,8)(6,7)(10,16)(12,17)(18,22)(20,24)(25,26,29,32)(27,30,35,33)(28,31,37,36)(34,38,40,39)(1,4)(2,3)(5,6)(7,8)(9,12)(10,11)(13,16)(14,20)(15,17)(18,19)(21,22)(23,24)(25,26)(27,30)(28,36)(29,32)(31,37)(33,35)(34,39)(38,40) involution — undirected(9,13,15,11)(10,17,16,12)(14,21,23,19)(18,24,22,20)(25,28)(26,31)(27,34)(29,37)(30,38)(32,36)(33,39)(35,40)(9,14,15,23)(10,18,16,22)(11,19,13,21)(12,20,17,24)(25,27)(26,30)(28,34)(29,35)(31,38)(32,33)(36,39)(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.