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