Brush the wicker piece with a soft metal brush to remove as much old paint as possible, as recommended by wicker refinishing expert Cathryn Peters. You can brush vigorously, but take care not to pull on the canes or damage the joinery.
Use an old knife or similar object to remove loose paint that is stuck in crevices. The piece does not have to be perfectly stripped, but do get rid of all loose paint.
Using medium grit sandpaper, sand the piece to smooth off the rough edges and roughen up the smooth areas so the paint will stick to the surface better.
Hose off the piece with water and set it in the sun to thoroughly dry. Allow a full day to get rid of the moisture.
Load a compressor paint sprayer with primer and spray the piece outdoors or in a well-ventilated area. Use a face mask. Alternatively, you can paint the primer on with a natural-bristle brush, but spraying is easier to cover all of the small crevices. Allow it to thoroughly dry (check the paint label for drying time) and apply a second coat. Allow this coat to thoroughly dry too. Aged wicker absorbs a great deal of paint, according to Cathryn Peters, so the priming process is important.
Load the compressor with the paint, and spray the piece of wicker. You can use traditional white, or any color you choose. If necessary, spray a second coat after the first coat has dried.
Allow the paint to cure for a week before you use the piece.