Sit comfortably with your eyes closed.
You will probably find that some colors are easier to visualize than others. Notice what each color feels like. You can expect each color to feel different. Here is a list of some of the correspondences that people often experience between colors and physical or emotional feelings.
Red
Red is associated with fire and heat. Visualizing red can help increase physical feelings of warmth and the emotions of passion and anger. Red can strengthen the blood and improve circulation, and it is associated with blood and courage. The human eye is capable of discerning hundreds of shades of red, and this capacity is reflected in the many metaphors associated with this color. Your meditation on red could invoke shades from nearly orange, to pinks, cerise, cranberry, and so on. Notice the shade that you envision, and look for that color in your wardrobe and your environment.
Orange
Orange is a color associated with health. I think of carrots and oranges, which are rich in vitamins A and C. I think of carnelian beads that feel cool to the skin, no matter how hot and humid the weather. I think of sweet, juicy peaches and Rocky Ford cantaloupe. According to Bill Stuber in Gems of the 7 Color Rays, orange is the color to use to stimulate vitality and joy. It provides the means to balance one's physical and emotional system, and to identify what needs to change to improve one's health. Meditation on the color orange will encourage a state of well being to manifest within you.
Yellow
Yellow is an active color. It is the color of the sun, of midsummer flowers and ripe corn. It is warm, but not flaming hot. Yellow may be more difficult to sustain in meditation that other colors. This may be because when we focus on yellow, we also allow our minds to open to the vastness of the sun, and thus lose focus. The complementary side of meditating on the color yellow is the potential to ground yourself. From a solid earth connection you can experience the vastness of the sun without harm. In the midst of the materiality, the color yellow opens you to the sun, the source.
Green
Meditating on the color green deepens your connection to your inner being. We rejoice in the spring when plants burst forth and surround us with multiple shades of green. We are stimulated to fruitful action by this color. This healing color can ease the pain of grief and sorrow. It can also deepen feelings of satisfaction and remove toxic factors on the physical, mental, emotional, and spiritual levels. Meditation on green can help you achieve greater success in all activities because it establishes a closer connection between conscious action and unconscious intention.
Blue
Blue is the color of the sky, of space. Meditation on the color blue enhances your mental capacity by clearing away the distractions that invade your thoughts. When you close your eyes, it may be easier to visualize violet or indigo than blue. Thus you may want to find something blue to focus on with your eyes open. Once you have developed focus in this way, blue meditation will come more easily. Some people find that blue encourages restfulness and sleep, so don't be surprised if this meditation makes you drowsy.
Indigo
Indigo is associated with alpha brain waves, and with intuition. This color is relatively easy to visualize with eyes closed. By breathing deeply and relaxing, you will learn to evoke the color easily. By visualizing indigo, you can alter your brain waves to increase alpha waves. With practice you can consciously will this state of mind. Many people feel rested and refreshed after this meditation. The muscles of the face and head relax. In this state a spiritual connection is made within you—you feel at peace. You will also feel more capable of accomplishing your goals.
Violet
You may find that when you meditate, particularly with your eyes closed, that you can easily visualize violet as you relax. Violet, like indigo, is often perceived when alpha brain waves are present. This color promotes the capacity to use different parts of your mind. It also creates avenues for communication without the pain associated with mental or emotional ruts. Violet can relieve headaches and other physical pains.
White
Meditation on white light is one of the most common color meditations. White light is associated with psychic protection, and with healing and wellness. Most people find it easy to imagine white light with their eyes closed. An interesting point about white light is that while it is used for protection, it does this by forming a strong connection, not by insulating against what is feared. White light is full-spectrum light, or, in other words, it integrates all the colors into one ray. This meditation stimulates the mental and sometimes moral integrity that make it possible to act selflessly.
Excerpted from Meditation for Beginners, by Stephanie Clement.