Please provide me some guidance on how to do japa and why ?
1. Is Mantra to be recited loudly, whispering or just in mind while doing Japa ?
2. I have been reciting Mantra in mind while at work, travelling etc. does it amount to Japa?
3. Is concentration / visualisation required while doing Japa as in Meditation ? Or just reciting mantra will amount Japa.
4. Is counting necessary in Japa ? Counting becomes difficult while doing Japa. Is there any significance for numbers like 108 , 1008 etc or the more is better.
5. How to measure Japa? Is is count, time spent or something else ?
5. What are the fruits of Japa and when can we expect and get them?
I am no expert but here are a few tips - chant mentally (initial few rounds can be done loudly), body should be perfectly still, breathing very slow and deep (rhythmic breathing is preferable), focus with one- pointed mind on the mantra as it is chanted mentally, best time is 3 hours before sunrise. Benefits of Japa are health, wealth and prosperity, and if you are so inclined possibly moksha too LOL.
The best book for a beginner on Japa is Japa Yoga by Swami Sivananda (Swamiji's book "How to attain success in Life and God-realisation" is a wonderful companion book)
Just two remarks:
Not necessary to do japa in night, people may be having family and work LOL. But it is good if japa is done same time every day. Perhaps it should be easy to do either in the morning or before sleep (or both).
It is VERY good to chant mantra mentally along the day - without mala etc. The best japa in fact is continuous one.
Finally, and VERY important - DO NOT DO japa for maerial benefits!!! And for sure NEVER in beginning. ONLY to get nearer to God, to have some of His grace...
Mantra may be recited loudly, quietly, or silently ~ the last being most auspicious.
Silent repetition of mantra at any time certainly qualifies as japa. Concentration on the mantra being applied is certainly preferable during japa.
Counting is not required during japa, and generally speaking, the more the better; although certain numbers (counted in one set or sitting) are more auspicious. 108 times, or any multiple or fraction of that amount (e.g. 27, 54, 108, 216, 1008, 21600, etc.) is generally considered most auspicious.
Japa is not really measurable in human terms. Although number of repetitions and time spent may give some indication, the degree of effect and speed of progress depends on many factors that are different for each individual.
The fruit of japa is tapas, the fire which burns all karma, and each individual has a different debt of past karma to overcome before "liberation" is a possibility. With devotion and determined effort, and the grace of the Guru, the goal may be achieved sooner ~ perhaps in this life, perhaps in the next, or maybe even tomorrow!
Japa can be done aloud if the mind is busy and silently as the mind becomes quieter. Silent Japa has several layers: first, you will still feel the vocal chords working, then you will be repeating the Mantra mentally and finally transcendentally.
You should repeat your mantra as often as possible during your daily life and not just during a formal meditation practice in front of your altar. All Mantra repetition is Japa but Japa done during a formal meditation practice is the most efficacious.
While performing Japa you should also concentrate on one of two focal points - either the Ajna chakra if you have a rational approach to life or the Anahata chakra if you have an emotional/devotional approach to life. In addition, the attitude with which you perform is Japa is very important. Your attitude should be peaceful, serene, and filled with dedication to your ishta-devata if you have one.
Counting is not necessary in Japa but as a disiplinary and focusing device you could use a mala which has 108 beads and therefore commit yourself to a certain number of malas of Japa. Eventually, the use of a mala will be unnecessary.
With regard to your questions about how to measure Japa and the fruits of Japa, you use mala or time as disciplinary devices only. The true measure and fruit of Japa is absorption in the Divine. Japa uses audible and inaudible frequencies to awaken dormant centres in the brain and psyche and to attune your psychological, physiological and spiritual faculties to that original and sustaining vibration of creation that some call God, Aum, Brahman, or Devi, etc. When you repeat a Mantra, you bring all aspects of your being consciously in tune with the Supreme Vibration as contained in the Mantra and eventually you come to identify with that Supreme Vibration and with the Divine ground from which it emerged.