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