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