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