Choose your pipe cleaner color and form into desired shape (remember you can cut and wire them together, especially for snowflakes!).
Tie a string or thread to the top of the ornament and tie the other end to the middle of a pencil so that it looks like a letter 'T' - there won't be much length between the pencil and the ornament, just enough to hang down from the top of the jar to the borax solution.
Fill a wide-mouth jar/container with boiling water (we typically use large canning jars; the size of your container will depend on the size of your pipe cleaner creation).
Add Borax in increasing amounts until water is cloudy even after the Borax is dissolved (this is why we use glass jars most of the time, although we have also made the mixture up in glass jars and poured it into empty margarine containers, etc, if their size worked better) - this part is a bit science, a bit art and may take some adjusting to get the levels right.
Balance the pencil across the top of the jar and suspend the ornament in the hot Borax mixture, making sure the pipe cleaner is completely immersed but does not touch the bottom or sides of the container.
Put jar in an undisturbed place; as the solution cools, crystals will form on the pipe cleaner.
The longer you soak it, the more crystals you will have and the less the original pipe cleaner will show through, so adjust time until you achieve your desired look - overnight will give you very thick crystals, a few hours will give you just a gentle glittery look.