Okay, the mother of all simple rituals! This is the one I did for Imbolc this year (2004). I like it. Straight and to the point.
Pour water in Cauldron to 1/4 of the way full. Place large pillar candle inside. Light the incense, and Cast the Circle.
Take up the Athamé and facing East, take a moment to center yourself and begin to cast the Circle. Visualize a white light coming from the tip of the athamé and with arms straight out, turn the blade point out, slowly turning clockwise the light following you.
When you return to the East bring the athamé back to you and say:
“As above, so below.” As you say this, visualize the light going above you and below you forming a perfect sphere.
Face the East again, and make the sign of the invoking pentagram in the air, saying:
"East, Power of Air,
Welcome to my Circle."
Face South, and while making the sign of the invoking pentagram, say:
"South, Power of Fire,
Welcome to my Circle."
Face West, while making the sign of the invoking pentagram, say:
"West, Power of Water,
Welcome to my Circle."
Face North, and make the sign of the invoking pentagram while saying:
"North, Power of Earth,
Welcome to my Circle."
Now, return to the altar and invoke the Deities:
"Brighid, Blessed Lady of Inspiration, Healing, and the Fires of
Creation.
Be with me tonight."
"Lord of the Sun, Bringer of the Light,
Be with me tonight as I honor the Blessed Lady, Brighid."
Light the Candle inside the Cauldron and meditate for a time on Brighid, the meaning of Imbolc, and the fires of creation.
When you are done, chant softly 3 times:
"Like Brighid, I will light: the fire of inspiration into other
worlds.
Like Brighid, I will light: the fire of the hearth in my home.
Like Brighid, I will light: the fire of healing at the holy well."
Make the libation to the Gods, and thank them for attending the Rite. Release the
Quarters and take down the Circle.
The ritual has ended