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