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