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)(27,33)(28,37)(29,31)(30,34)(32,35)(36,39)(38,40) involution — undirected(1,2)(3,4)(5,7)(6,8)(9,11,15,20)(10,16,17,13)(12,18,22,24)(14,19,21,23)(25,27,32,36)(26,33,35,39)(28,38,29,34)(30,37,40,31)(1,3)(2,6)(4,7)(5,8)(10,17)(13,16)(14,21)(19,23)(25,28,32,29)(26,31,35,37)(27,34,36,38)(30,33,40,39)(1,4,5,6)(2,3,7,8)(9,12)(10,14)(11,18)(13,23)(15,22)(16,19)(17,21)(20,24)(25,29,32,28)(26,31,35,37)(27,34,36,38)(30,39,40,33)(1,4)(2,3)(5,6)(7,8)(9,13,15,16)(10,11,17,20)(12,19,22,23)(14,24,21,18)(25,30)(26,34)(27,31)(28,39)(29,33)(32,40)(35,38)(36,37)(1,2)(3,4)(5,7)(6,8)(9,14)(10,12)(11,19)(13,24)(15,21)(16,18)(17,22)(20,23)(25,31)(26,28)(27,30)(29,35)(32,37)(33,38)(34,39)(36,40) 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.