Sand the entire surface of the wood desk with 220-grit sandpaper to smooth the wood. Sand with the grain of the wood. Wipe the desk clean of sawdust with a cloth.
Apply a coat of latex stain-blocking primer to the wood desk with a clean brush. Allow the primer to completely dry.
Sand the wood desk again with 220-grit sandpaper and wipe the desk clean with a cloth.
Brush a smooth, even coat of semigloss latex paint onto the wood desk. Allow the coat to dry and lightly sand the wood desk with 220-grit sandpaper. Apply a second coat of paint to the wood desk and let it dry.