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