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