It’s hard to hammer in small nails and brads without hitting your fingers. But you can simplify this task with the help of a pencil.
Take a utility knife and cut a slit down the center of the pencil eraser. Then press the nail into the slit. Use the pencil as a handle to hold the nail into position, then tap it in with the hammer.
After a few taps, pull the pencil away and finish hammering in the nail.