How can I properly finish a drywall corner to achieve a smooth and professional-looking result?

To properly finish a drywall corner for a smooth and professional look, follow these steps:

1. Apply joint compound to the corner using a taping knife.
2. Place a metal corner bead on the corner and press it into the compound.
3. Apply a second coat of compound over the corner bead, feathering the edges.
4. Sand the corner smooth once the compound is dry.
5. Apply a final coat of compound, feathering the edges again.
6. Sand the corner one last time for a seamless finish.