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