Clean the wicker piece you wish to paint. Brush off all dirty and cobwebs and carefully wash off any mold and mildew that may have grown on it.
Use a soft wire brush to scrape off the old paint, if it is flaking. Don't worry about removing all of the paint, just any areas where the paint is already coming off, to ensure a smooth coat of new paint.
Sand any rough areas on the wicker piece. Run a fine gauge sandpaper over the whole piece to rough up the surface and help the new paint adhere better.
Apply an oil-based wood primer to the entire piece, following the manufacturer instructions. The primer is especially important if you are making an extreme color change. Allow the primer to dry.
Place the piece on a large drop cloth in a well-ventilated area, preferably outdoors. If you are concerned about paint getting on other surfaces, construct a temporary paint booth by cutting one side from a large cardboard box, such as an appliance box, and put the item in the box before painting.
Paint the piece using two coats of outdoor spray paint or use outdoor house paint in a compressor sprayer. Move the sprayer back and forth with short, even strokes, covering the piece completely. Keep the sprayer 8 to 10 inches away from the wicker piece to prevent drips and uneven coverage.
Allow the paint to dry completely between coats. It can take up to two weeks for the paint to completely cure.