In The Hour of Mars, On The Day of Belzebuth, the Moon a Crescent:

On Tuesday morning I woke up groggily to my phone alarm while it was still black out. Artie perked herself up in front of me on the bed and straightened her spine in a long yawning stretch. I felt the same apprehension as to the prospective of waking, so hit the coffee machine and expected to waste some ten minutes sipping liquid awareness from my cup between the arms of my chair. I was happy that after this working there would be no more early mornings in the near future, but today was unquestionably the most important preparatory working for the ceremony. I needed to be fresh.

Once it had cooled, I took a deep sip of the coffee and swirled it around in my mouth. Then I fished through my tools on the workbench and brought out the pen and ink, the parchment, and the lancet, as well as my copy of the Grimorium Verum itself.

I wasn't squeamish about the sight of blood or a little bit of pain, but there was still something trepidatious about my approach as I used the lancet to draw it from my finger. It was like a game of chicken I played with myself, gently pushing the razor firmer and firmer against my flesh until finally it broke the skin.

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I withdrew the lancet and held my pierced tip over the open inkwell. Just a few drops was all it would take to contaminate the ink with my essence. Blood in the goetic workings is a means to establish a link, not ambrosia for the damned.

The parchment was the most important single object in the ritual. The Grimorium Verum prescribes an elaborate process of animal sacrifice, curing, and purification, but this was beyond the means of the vast majority of modern practitioners. I had bought a few sheets of the highest quality vellum I could from the local art store that I had set about fumigating and purifying, as with any of the other tools in the book, but this deviance from orthodoxy still nagged at me. I liked to be a traditionalist where I could.

I set the parchment down on the table surface, withdrew my copy of the grimoire, and set about inscribing the demonic seals I would use in the evocation.