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