Set up an altar for the power in question. On this altar place all signs, sigils, metals, stones, images, herbs, mirrors and other things that can connect you to the spirit you seek oneiric union with.
Consecrate candles in the name of that spirit. Carve sigils and invocations on those candles that call forth the currents needed and dress the candles with your own lunar blood, musk oil and dried and powdered Artemisia Vulgaris and Artemisia Absinthium.
Make also an infusion with a teaspoon of Artemisia Vulgaris and a teaspoon of Absinthium. Let the infusion cool down and pour it into your ritual Chalice and in that infusion blend nine drops of blood from your left hand's thumb and two drops of your lunar blood. Place the Chalice on the sigil of the spirit in question.
In front of this altar contemplate the sigils and focus on the power that you need to contact in your dreams. Write and recite invocations to the spirit and, with your mind's eye, create a form for it to manifest its powers through. Light one of your Dream Candles (these are the consecrated and dressed candles, and not your standard central flame or altar candle) and call upon the forces that you yearn for.
Point the Dagger of Will and Fire towards the chalice and trace the pentagram of Water/The Western Throne. Vibrate the name and formulae of the spirit in question and watch the pentagram burn black. Lower the dagger of Will into the chalice of Desire and let your will to unite in oneiric communion flow through the blade with which you stir the elixir in an anti-clockwise motion.
Invoke the spirit and tell it to bless the elixir so that it can open the oneiric gates and bring you to the twilight crossroads where you can bask in the dark light of your gods.
Drink the bitter elixir, invoke the spirit again and proclaim to it once again your will to dream of it, and meditate on the flame of the dream candle. When you feel ready to enter the oneiric gates, give praise to your gods and extinguish all flames, but let the dream candle burn.
Make your bed on the floor in front of the altar and in the light of the dream candle. Chant the formulae and adore the form that you have created with your mind's fire, until you pass through the gates of sleep...
If you are blessed your desire will be fulfilled and the spirit that you seek contact with will come to you and let you learn what you can learn from it.
The whole process can be repeated once every week, with new dream candle and new elixir.
It can even be done without the elixir when you have opened the oneiric gates. But the dream candles are always good to use, for many different reasons...
The best time for all these things is when the moon is dying, and if possible let the whole work culminate on the night when the moon is black.
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