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