Liber Spirituum Potentissimorum (Compendium Magiae Nigrae)

6.) The Master The lead practitioner or ritual leader should either be alone; or if there are to be several, the number must always be odd.
7.) A secure and solitary place is required; if the operation is performed in a house, let it have a suitable chamber facing the east, and let either a door or a window be left open. Nor should there be more persons in the house than those who belong to the operation. For this reason, it is always safer and better that the experiments be performed under the open sky, in woods, and in wildernesses or meadows not subject to the sight, hearing, or disturbance of men. For any operation whatsoever, let a fumigation Incense or smoke-offering be employed from the following:

A faint, large triangle is sketched in the center of the page, containing the following list of ingredients.

8.) Let the experiments be performed on the days of Mercury Wednesday or Friday; either at night, in the first or sixth hour after sunset; by day, however, they must be performed in the very hours of the planets Venus or Mercury.
9.) Before the operation, the Master should deliberate well on what business he wishes to transact with the spirits, lest in the middle of the experiment there be confusion or disturbance.