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