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