The foundation is the most important part of the temple. Its foundation has to rise out of the earth just as the mound rose out of the primordial ocean of Nun. Originally it was the king's responsibility to excavate the site, but today this isn't necessary. But you can do the following:
Do not invoke any God here. No Gods are directly involved in the initial stages making of the temple.
Take some watery mud and mix with straw and form four mud bricks. Now you can either make them part of the temple foundation itself or just place them in the four corners once it is finished. Either way it is to symbolize strength and protection as the "cornerstones" of the building.
Next sprinkle sand on the foundation of the temple to symbolize the primordial virgin soil. (It can be later swept away once the purification is done.)
Now place objects of protection in the four corners of the foundation to symbolize protection against all those who would wish to tear the building down or have it harmed in any way.
The final act of this rite is to tamp down the foundation to symbolize the firmness of the foundation.
Now for the purification and preparation of the temple or altar....
First you need to prepare some natron (which is a combination of baking soda and salt) and incense (pine resin being the most appropriate). Go through each room of the temple (or around the altar) sprinkling natron and censing visualizing the all negative energies leaving the temple/altar.
Once that is completed you need to "bring to life" the statues and wall paintings with an Opening of the Mouth ceremony. You can either have two priests impersonate the Gods involved or do this alone. You can also invoke the deities into you if you know how.
The "opener" is Ptah, the "openie" is all the other god images of the temple/altar. You need an various sculptors tools for this rite. Touch the tool to the part that needs to be open. Say the following:
Ptah/opener: Ptah takes his blade to open the eyes. Sokar/openie: Sokar/openie opens his/her/ eyes. Ptah/opener: Ptah takes his pick to open the nose. Sokar/openie: Sokar/openie breathes deeply. Ptah/opener: Ptah takes his chisel to open the mouth. Sokar/openie: Sokar/openie opens his/her mouth.
Now this time as Anubis the opener touches the openie with the adze and repeats the opening.
Next offerings are presented around the altar with a prayer in hopes that all that has been done has been done to the satisfaction of the Gods.
Finally the opening is done again. This time to the temple/altar as a whole unit. From now on the temple/altar is a living, active being as the embodiment of the Netjer's vital energy.
