Use a nail set to tap a trim nail just below the wood's surface, so the nail head can not be seen. This tool is used by many experienced painters to produce a smooth finish.
Use a putty knife to fill in and smooth putty and to remove remove old caulk.
Applying new caulk with a caulk gun make the process of applying the caulk to the cracks between the wood trim and the wall easier.
Placing painter's tape along the edge between the trim and the wall will help the avid painter keep paint on the trim and off the wall.
A 1 1/2 to 2-inch sash or angled brush can be used to paint a clean line on the top edge of the wood trim. A 2 to 3-inch straight-edge paintbrush is best for painting the flat surface of the wood trim.
Sandpaper is used for sanding debris from the wood trim. It can also be used to rough up the trim's surface, making paint adhere easier and longer. Sandpaper comes in various grades that vary from course and rough to smooth and nearly soft.