Sadhana means daily spiritual practice. It is the foundation of all spiritual endeavor. Sadhana is your personal, individual spiritual effort. It is the main tool you use to work on yourself to achieve the purpose of life. It can be done alone or in a group. Sadhana is whatever you do consistently to clear your own consciousness so you can relate to the infinity within you. Before you face the world each day, do yourself a favor and tune up your nervous system and attune yourself to your highest inner self. To cover all your bases, it will include exercise, meditation, and prayer.
During what are called the “ambrosial hours” (the two and a half hours just before sunrise), when the sun is at a sixty-degree angle to the Earth, the energy you put into your sadhana gets maximum results. Your world is quieter. It’s easier to meditate and concentrate before the hustle and bustle of the day begins. If you absolutely cannot get up early in the morning to do sadhana, then do it some other time! Doing sadhana at any time of the day or night will benefit you. (Kundalini Yoga: The Flow of Eternal Power by Shakti Parwha Kaur)
Develop a regular sadhana and you take control of your life. Develop a deep sadhana and you open the doors of experience. Commit to meet your higher Self each morning and your decisions and your life become original; your life will bear the signature of your soul; your radiance will express the meaningful intimacy of the Infinite in each moment. Immerse yourself in the joy of victory that comes from starting each day with a powerful sadhana and every challenge becomes opportunity. (Sadhana Guidelines)
Excerpt from 3HO.org