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