Ways to open up psychic pathways: Some of the powerful ways to work with the psychic pathways requires one go subtle. Kriya pranayama, which is one of the techniques of Kriya yoga works directly with the psychic pathway. If you are able to feel and work with the whole of your subtler energy body (as in Vipassana), that also opens up the sushumna in a wonderful way. To feel the energy body, one has to initially work with breath. Working with the breath is a whole system in itself and can give wonderful results.
Working with the breath: Keep your mind inside the nostrils and feel the touch sensation of the air moving inside the nostrils. There is no need to move in and out with the breath. Let the awareness be still on the touch sensation. Feeling the sensation of the touch is the importance here. It is a wonderful way to meditate. You stay with the reality, not imagining something. If the mind wanders away, just get it back. You can do this at all times and not only when you sit to meditate. But, sitting for a meditation greatly helps in making a quick progress. Observing the breath at all times is very important to get established in the technique. As you keep on observing the breath, you shall feel the breath getting more and more feeble and it shall settle down. At that stage, stay feeling the gap between the breaths. Gradually the gap between the breath shall increase and take you into deeper levels of stillness. Just stay in that stillness, observing the suspended state of breath. You can do this amidst your daily core of activities. Practising it at all times is the secret to quick success.
Don't expect any magic to happen in a day or two. Have patience and practice regularly. Food is an important factor. Be aware of what you feed the body.
A wonderful writing from a breatharian, that may inspire you: http://www.ethereallights.com/breathless.html
When one is in a breathless state, more of cosmic energy enters the being and the transformation/shift happens.
