Get up between 3 am and 5 am. This is Brahmamuhurta – the Auspicious Early Morning Time. Everywhere is Silence. Nature herself is at Peace. Meditate. Retire peacefully into the inner chambers of your heart. – Swami Sivananda
Get up at Brahmamuhurta and practice meditation. Do not fail at any cost. Brahmamuhurta is the morning period from 3 to 5 a.m. It is very favourable for meditation. The mind is quite refreshed after good sleep. It is quite calm and serene. There is the preponderance of Sattva or purity in the mind at this time. In the atmosphere also. Sattva predominates at this period.
The mind is like a blank sheet of paper or a clean tablet and comparatively free from worldly Samskaras or impressions at this period. Raga-Dvesha currents have not yet deeply entered the mind. The mind can be moulded very easily at this period of the day. You can charge the mind easily with divine thoughts during Brahmamuhurta.
Further, all the Yogins, Paramahamsas, Sannyasins, aspirants and the Rishis of the Himalayas start their meditation at this period and send their vibrations throughout the world. You will be immensely benefited by their spiritual currents. Meditation will come by itself, without any effort. It is a terrible spiritual loss for you if you do not utilize this period of the day in divine contemplation and if you snore at this time. Do not become a Kumbhakarna. Become a Yogi like Jnana Deva.
In winter it is not necessary that you should take a cold bath. A mental bath will suffice. Imagine and feel, “I am taking a bath now in the sacred Triveni at Prayag or Manikarnika at Benaras.” Remember the pure Atman. Repeat the formula, “I am ever pure soul.” This is the most powerful wisdom bath in Jnana Ganga. This is highly purifying. It burns all sins. Answer the call of nature quickly. Cleanse the teeth quickly. Do not waste much time in cleansing the teeth and taking bath. Be quick. Hurry up. Get ready soon. The Brahmamuhurta will pass quickly. You must utilize this precious time in Japa and meditation.
Wash the face, hands and feet quickly. Dash cold water on the face and on top of the head. This will cool the brain and the eyes. Sit in Siddha, Padma or Sukha Asana. Try to climb the supreme height of Brahman, the peak of divine glory and splendour.
If you are not in the habit of getting up early, have an alarm timepiece. Once the habit is established, there will be no difficulty. The subconscious mind will become your willing and obedient servant to wake you up at the particular time.
If you are a subject of chronic constipation you can drink a tumbler full of cold water or lukewarm water as soon as you get up after cleansing the teeth. This is Ushah-pana treatment in the science of Hatha Yoga. This will give you a good motion. You can drink Triphala water also. Soak two Harads (myrobalan), two Amalaka and two Thandrikkai in a tumblerful of cold water at night. Drink the water in the morning after cleansing the teeth. You can keep a readymade powder of these drugs and put one or two teaspoonful in the water.
Cultivate the habit of answering the calls of nature as soon as you get up from bed. If you suffer from incurable, old constipation, due to old sins, do meditation as soon as you get up. You can answer the calls after finishing your morning meditation with the help of a cup of hot milk.
As soon as you sit do Japa and meditation. This is important. After finishing your Japa and meditation you can take to the practice of Asana, Pranayama and study of the Gita and other religious books.
During Sandhya time, or dusk, is also favourable for meditation. During Brahmamuhurta and dusk, Sushumna Nadi flows readily. You will enter into deep meditation and Samadhi without much effort when Sushumna Nadi flows. That is the reason why Rishis, Yogins and scriptures speak very highly of these two periods of time. When the breath flows through both nostrils, know that the Sushumna is working. Whenever the Sushumna functions sit for meditation and enjoy the inner peace of Atman or Soul.
Repeat some divine Stotras or hymns or Guru Stotras or chant OM twelve times, or do Kirtan for five minutes before you start your Japa and meditation. This will quickly elevate your mind.
From the DLS article Brahmamuhurta – Best Time for Meditation by Swami Sivananda