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