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