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