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