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)(11,13)(12,16)(14,15)(17,22)(18,21)(19,23)(20,24)(27,33)(31,34)(35,39)(38,40) involution — undirected(2,5)(6,7)(10,15)(11,17)(12,19)(20,21)(25,26,30,28)(27,34,33,31)(29,32,37,36)(35,40,39,38)(1,2)(3,6)(4,5)(7,8)(10,15)(11,17)(12,19)(20,21)(26,28)(31,34)(32,36)(38,40) involution — undirected(1,3)(2,6)(4,8)(5,7)(9,11,14,17)(10,13,15,22)(12,18,19,24)(16,21,23,20)(25,27,30,33)(26,31,28,34)(29,35,37,39)(32,38,36,40)(9,12,14,19)(10,16,15,23)(11,18,17,24)(13,21,22,20)(25,28,30,26)(27,34,33,31)(29,32,37,36)(35,38,39,40)(9,13)(10,17)(11,15)(12,20)(14,22)(16,18)(19,21)(23,24)(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.