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