The best way is to use ditto to bread with the other pokemon. To the egg appear quickly after putting the two pokemons together get your bike and go biking from the day-caro to skyarrow bridge. Make 6 laps in the bridge and go back to the day-care. The man will say that the egg has appeared.
I think that is not good that the pokemons that you find in battle subway dont appear in your pokedex. And sometimes the game made a very hard trainer to defeat and there goes your progress.