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