How should I properly prepare sand plywood before painting it?

To properly prepare sand plywood before painting it, start by sanding the surface with fine-grit sandpaper to smooth out any rough areas. Next, wipe down the plywood with a damp cloth to remove any dust or debris. Apply a primer to help the paint adhere better and allow it to dry completely before painting. Make sure to use a high-quality paint suitable for plywood for best results.