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