Sealing the aura is a daily practice of protecting the aura from external negativity. It is an excellent practice to seal your aura daily, particularly if you are going to be doing hands-on healings.
Method A (if you have little time)
Weave light around yourself in a continuous swirling motion until you feel energized and centered.
Breathe deeply with your eyes closed.
Now imagine a shaft of golden light entering the top of your head.
As you breathe in, breathe in this golden light, right down to your heart and solar plexus.
Breathe in to a count of 3, hold for 3, breathe out to a count of 4, and hold for 4.
Sense the power building in your body as you continue to breathe this way for a few minutes.
Now imagine your Aura, like an egg shaped cocoon surrounding your body.
As you breathe out, imagine the energy you have been building up begins to flow out into this cocoon, filling it with golden light.
Breathe in the golden light from above, and breathe out into the cocoon, in the same rhythm as before.
Picture the outer edge cocoon becoming like a thick transparent shell, allowing only positive influences to pass through.
~from Maat's Book of Shadows