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