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