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