Fill your steamer with water. Rent a wallpaper steamer at a local wallpaper store. Ask for a quick demonstration before you leave the store. Let the steamer heat up until steam begins to come out.
Lay the head of the steamer on the paint and hold it there for 30 seconds to one minute. The heat from the steamer and the moisture will work to soften the paint and peel it from the wood. Press firmly to make sure the steam is penetrating the paint.
Move the steamer head aside and use the putty knife to check for softness. If the paint peels easily, the area is ready. If the paint does not come up easily, keep the steamer in place for a bit longer.
Work your putty knife under the paint. Holding the knife at a 45-degree angle, push the paint up and off the wood in a single strip. The paint should not come off in small pieces. Paint coming off in small pieces means the steamer isn't hot enough or you haven't left it on the paint for long enough.
Move the steamer to an adjacent spot and repeat the process. Work in a methodical way, making sure to get all of the paint off of a spot before you move to the next area.