Old-school ritual preparations involve laying out a space – either a permanently established ritual area (shrine, sacred space, summoning circle, wizard’s lab, and so forth), or a temporary space that has been sanctified for the spirit’s presence. Technomagickal practices involve setting up containment grids, extradimensional portals, trans-dimensional fluctuation chambers, and other methods that bridge the space between Consensus Reality and the weird regions of the alien visitors.

For obvious reasons, advance prep also contains protective measures: wards, sigils, powerful allies, prisons for the entity if it happens to get out of hand. High Ritual practices – the ones most traditionally connected to such matters – feature elaborate diagrams that must be inscribed with mathematical precision and ritual intent. Shamanic practices involve simpler measures, but depend heavily upon the personal power of the shaman himself.

Game-wise, the Storyteller may have the player make a series of rolls to prepare the space properly… or might even make those rolls herself, in order to keep the final condition of the space a secret from the player. The exact rolls and Traits will depend upon the mage’s practice and the sort of space involved, but generally involve the knowledge to set up ritual or technological space properly. A failed roll… or worse, a botched one… can have nasty consequences down the line. If you’re summoning one of the Veiled Sentinels of the Onyx Causeway, after all, you’re not going to want to screw up the incantation or forget to seal the pentacle…