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