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