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