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