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