Use a paintbrush to paint the solid metal frame of the compressor in a color that matches the house or building. This allows it to blend in better, instead of clashing with the rest of the property. Avoid painting the fins on the compressor.
Plant shrubs around the compressor, at a distance of at least 24 inches, so that they do not block the airflow around the compressor. Also, create an opening so that you have clear access to the compressor to clean the fins and clean away the leaves and other debris that fall around the compressor. Otherwise, the debris chokes the compressor's airflow.
Measure the compressor's length and width, using a tape measure, and install an appropriately sized lattice screen or lattice fence around the perimeter of the compressor. Erect the barrier 24 inches away from the compressor to allow for unobstructed airflow.