Take the sponge and thoroughly wash the wicker item with warm water and added bleach. Use enough bleach to make a strong mixture. Use the toothbrush to get into crevices and remove as much dirt and mold as possible.
Rinse the wicker with a garden hose and allow a good 24 hours to dry. Place the item, such as a chair, upside down to allow water to run off and not seep into any cracks. Set a table on its side so it will dry more efficiently.
Spray or brush two light coats of the oil-based primer onto the item. This creates a surface that allows the acrylic paint to adhere better. Let it dry according to the manufacturer's instructions before painting.
Spray paint the item using smooth, steady strokes. You can spray paint in any direction: across, up and down, and around shapes. Just make sure to cover the entire item.
Let dry for one hour before adding a second coat, if needed. Once it is finished allow at least 24 hours to dry.