We all have different routines when doing spells and rituals. Below is a basic guideline that you may find helpful if you feel that following a structured routine will work best for you, or if you aren't sure where to start and need a guideline. These are not set in stone and can be changed to suit your needs.
Ritual Preparation -- Choose a time. Decide the intent. Choose an aspect of the Divine, if you wish. Decide how to raise energy (i.e., dancing, chanting, drumming, etc.) Choose how to cast and close the circle.
Cleanse Yourself and Your Magickal Space -- You can do this with a ritual bath for yourself, or through meditation to still and focus your mind. You can cleanse your space with your magickal broom or with incense or burning herbs.
Cast the Circle -- Starting at the North side of the room, point your finger or wand and say the following as you imagine white light energy streaming forth from your finger and forming a circle around you:
I cast this circle to create a sacred space.
No unwanted energies can enter this space.
The circle is now cast! So mote it be!
By the time you've walked three time around the circle, you should be finished saying that. You may also choose to sprinkle salt or water on the ground around you or in the four corners.
Invocation of the Divine -- Invoke the Deities by asking them to join you for your magical workings. ("God and Goddess, I ask that you join me here to assist with my magical workings.")
Statement of Purpose -- This is simply to tell the Divine why you have called Him/Her to the circle and what you are trying to accomplish.
Magickal Working -- Raise energy, through chanting or drumming or however you have chosen to do so. Direct or channel this energy by using candles, herbs, stones or whatever other correspondences you found to fit your specific need. Ground your energy when you have completed the working.
Cakes and Wine (optional) -- Eat a small piece of bread or cookie and drink a little wine, milk, or juice to help restore your energy.
Thank the Divine
Close the Circle -- Starting from the West, walk widdershins (counterclockwise) around the circle three times as you say:
The circle is open, but never broken.
So mote it be!
Merry meet and merry part,
and merry meet again!
SOURCES: The Wiccan Garden & Everything Under the Moon