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)(11,19)(12,21)(13,18)(14,16)(15,22)(17,23)(20,24)(25,26)(27,36)(28,34)(29,30)(31,33)(32,35)(37,38)(39,40)(2,6)(3,7)(9,11,14,22)(10,15,16,19)(12,18,23,20)(13,21,24,17)(25,27,32,31)(26,33,35,36)(28,37,30,40)(29,38,34,39)(1,3)(2,4)(5,7)(6,8)(10,16)(13,24)(15,19)(17,21)(25,28,32,30)(26,34,35,29)(27,37,31,40)(33,39,36,38)(1,4)(2,3)(5,8)(6,7)(9,11)(10,15)(12,20)(13,21)(14,22)(16,19)(17,24)(18,23)(25,29)(26,28)(27,38)(30,35)(31,39)(32,34)(33,37)(36,40) involution — undirected(9,12,14,23)(10,17,16,21)(11,20,22,18)(13,15,24,19)(25,30,32,28)(26,29,35,34)(27,37,31,40)(33,39,36,38)(9,13,14,24)(10,18,16,20)(11,21,22,17)(12,15,23,19)(25,31,32,27)(26,33,35,36)(28,37,30,40)(29,39,34,38)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.