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