Start by removing any plastic labels from the bottle.
Apply any decorations you'd like, such as paint or beads.
Cut a piece of wire about three times the length of the bottle.
Twist the wire around the bottle, creating a cradle to hold it from the tree.
With the end of the wire twisted into a hook at the bottom of the bottle, hang the bottle. Make sure the wire is strong enough to keep it secure.
Take the bottle down and fill it with bird food. Consider which birds you want to attract (hummingbirds, blue jays) in choosing which bird food.
Fix a feeding tube to the mouth of the bottle.