Colours are modulations of light and through them, entities working in stones, plants, animals and humans manifest themselves. By concentrating on colours, you can bring them alive in you: they help you develop virtues related to them and they support you in your endeavours.
Remember to use the means nature offers you to connect with the spiritual world. Colours are one of those means. Take the colour blue for example- it is the colour of peace and truth. From time to time, immerse yourself in this colour. Imagine you are surrounded by blue rays and feel them permeate you: little by little, you will feel a deep sense of peace overcome you.
This deep peace will at last silence your heart and intellect and will help you free yourself from your greed, prejudice and bias, and everything will become clearer to you. Heaven is reflected in your soul as if on the surface of a still lake, and with this deep sense of peace you will contemplate truth.
Omraam Mikhael Aivanhov Daily Meditations