Before you continue with any other spells, you must ensure that you are in a negative free zone, and this does not only include the circle, but all other parts of your residence. You must be cleansed spiritually and then rid all negative energies. To start, a simple thing to do is as follows:

Charge a pewter dragon's claw which holds a crystal or glass ball with your personal energies after meditating.
Place it above an entrance door into your house or apartment.

By doing this, it will ensure that no more negative energies can enter your house whether cast, sent or roaming.

While burning the incense that best assists your concentration and energy channeling visualize a triple circle of purplish light around your body while chanting:

I am protected by your might,
O gracious goddess, day and night.