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