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