Blot up excess moisture from urine stains with absorbent paper towels, old newspapers or rags. The more urine that can be removed from the fabric when it is fresh, the easier it will be to eliminate the odor.
Add small amounts of water to the borax until a thick paste has formed. Create as much of a paste as necessary to thoroughly cover the size of the urine stain.
Rub the borax paste into the urine stain so that it penetrates the fabric and covers the entire affected area.
Let the borax paste dry onto the fabric so that is has a chance to neutralize the urine odor from the furniture. Once dry, vacuum the borax from the upholstery using the attachments on your vacuum cleaner.
Smell the fabric to see if there is any lingering urine odor in the furniture. If so, repeat the above process until the smell has been completely eliminated.