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