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Select water-based wood filler, primer, and paint if the item you are repairing is kept indoors, or solvent-based wood filler and oil-based primer and paint if the item will be placed outdoors. You'll also need craft sticks, disposable plates, PVA glue, wood glue, 120-grit sandpaper, and paintbrushes or rollers. Gather old clothes, rags, a sheet or drop cloth, painter's tape, and a paint stirrer as well. The craft sticks will provide a support for you to apply the wood filler to. Inspect the size of the hole and decide how many craft sticks it would take to cover it.  For example, if a hole can be filled by 3 craft sticks, lay them flat on a work surface side by side. Pour glue over the back of the 3 craft sticks. Place 3 more craft sticks on top of the first 3 to create a strong layer that's stuck together properly. The amount of craft sticks you'll have to use depends on the size of the hole. Give the glue 10 to 15 minutes to dry. Place the glue around the border of the hole in your wood. You should lay the craft sticks on the side they won't be seen from. If you're filling a hole in a cabinet, wall, or a wardrobe, place the craft sticks on the inside of the hole. If you're covering a hole in a wall or wood that you can't place on a flat surface, you might need to hold the craft sticks for 5 minutes so they stick to the glue.

Summary:
Gather your materials. Glue craft sticks together to cover the hole. Place the craft sticks on the back of the hole and secure them with wood glue.