When it comes to attempting to treat insomnia using energy healing, the first thing one should do is to try to remove the energy from your head and channel it into the ground. Most stress and anxiety, which are the primary causes of insomnia, are caused by excessive thinking which results in being chaotic and not well grounded.
To facilitate the process of grounding energy and removing it from your head try using Black Tourmaline, Black Quartz, Smoky Quartz, Pyrite or Hematite.
Crystals and gemstones that can be used to assist with treating insomnia should generally be chosen intuitively and can vary largely based on specifically why a person has a hard time sleeping.
Once the root cause of the insomnia is established, specific stones can be picked which correspond to those causes. For example, sleeping with Charoite and Amethyst is often used to help reduce fearful dreams and nightmares; Mangano Calcite and Kunzite can contribute to a safe feeling which can help one fall asleep easier; Smoky Quartz, Lithium Quartz and Lepidolite can calm chaotic emotions which can make falling asleep easier.
Some stones which are generally used as sleeping aids include Amethyst, Howlite, Nephrite Jade, and Herkimer Diamonds.
Other crystals and gems including Aquamarine, Blue Chalcedony, Blue Topaz, Blue Lace Agate, and Celestite have also been known to have been used in this regard.
Understanding the root cause of your insomnia can help you choose a stone, but as with other crystal healing choices, using your intuition and choosing a stone based on your feelings is generally the best way to go. Most of the time, if you open up your feelings, the right crystal for your needs will become clear.