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