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