In preparation for visualization, one should ground first.
To ground is to establish a connection to the energy of the earth.
Grounding helps to prevent the body from becoming overly stressed. It helps to keep your energy system safe when you are doing spiritual work or magick. It can rid the body of excess energy at the end of a spell or ritual, and prevents you from feeling agitated or over tired after a magickal working.
Grounding may be done before or after a ritual, or both.
A simple way to ground is just to sit with your palms on the earth. Feel the energy flow from the earth into your body from your palms. The energy flows up your arms, into your body. Feel the energy circulate through your body and back to the earth through your palms. Visualize the energy moving into the earth. Feel all the excess energy you may be carrying flow into the earth.
If you are in a home, sit on the floor and feel the energy go down past the foundations of the house and enter the earth.
The eating of fruits and vegetables after grounding should help also, and can never hurt.
One of the best methods to achieve grounding is the Tree of Life Exercise below.
The Tree of Life
Sit or stand with your body extended and erect. Breathe deep and with a rhythm. Feel your spine straighten.
Imagine your spine is the trunk of a tree. Feel tall and strong.
Feel your feet change to roots, strong, healthy and deep.
Branches from the top of your tree sweep down, as a weeping willow might, to touch the ground below.
You will feel the energy of the earth pulsing around your roots. Pull that energy toward you. Feel the power moving into you. Each breath you take draws the power further up, into your spine, the trunk of your tree.
The power of the earth rises up to the crown. Feel the energy as it moves from the crown of the tree down the branches, to return to the earth.
Take a deep breath. Feel the energy travel back to the ground. Now relax.