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