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