Spread a plastic drop cloth below the wall where you'll be painting.
Mix a dark color of interior paint and use a roller brush to paint over the bad spackling. Dark colors help hide the shadows in spackling where the wall surface is uneven. Cover the entire wall evenly.
Apply a second coat of paint with a paintbrush to cover the spackling cracks and crevices the roller brush was unable to reach. Paint the entire wall with a second coat.
Hang drapes or curtains around windows where bad spackling is present on the adjacent walls. The fabric conceals blemishes in the wall.
Cover smaller areas of spackling damage with framed prints or pictures, using the hammer to mount wall hangers.
Rearrange lamps and lower the lighting in the room to make the spackling damage less obvious.