Look at your thermometer every day. Watch for it to lower to 32 degrees Fahrenheit, which is water’s freezing point.
Attach a sprinkler to a water hose. Place the sprinkler close to a tree, a fence or a post. Although you can create icicles on your roof or window sill, you want to prevent ice from building up in these areas as it can cause roof or window leakage. Make sure the water will mist up in the area you want the icicles to form, when you turn on the sprinkler. Otherwise, place it closer to the object you want to form the icicles on. Place the sprinkler in the tree or on the fence to get the water to flow on it, if necessary.
Turn on the sprinkler just so it slightly mists the area you want the icicles on. If there is too much flowing water, it wont freeze. Leave the sprinkler on during the night.
Look for icicles on the object you misted in the morning. Watch the long dagger-like ice shapes sparkle and shine in the morning sun.