When looking for a suitable location for your retreat it is important for the place to be somewhere pleasant where you have the feeling that you want to stay.
First you need to do preliminary practices to pacify hindrances that may arise while abiding in retreat.
Your object of shi-nä can be either self as the deity or tum-mo. It is good to combine the generation stage with attainment of shi-nä, then you can do the two things at the same time. It is good to read Geshe lamrimpa’s book that explains his experience of shi-nä – the proper diet and conditions. Some of this advice may not be in the Lamrim Chenmo. For general explanation and guidelines for shi-nä, rely on the Lamrim Chenmo and Liberation in the Palm of Your Hand.
Every day, you need to do many prayers to complete the meditation, and also to accumulate a lot of merit. When the meditation is progressing you can cut down the prayers, but at the beginning do many mandala offerings and request to achieve the Three Great Purposes. When you reach the third or fourth stage of mental development, the main object is to complete the attainment of shi-nä and you can begin to gradually cut down the number of prayers. At the time your mind is stabilized in virtue, if you try to do prayers etc., they may distract you from shi-nä and that is not useful. So, with the purpose to attain shi-nä, cut down the prayers, not all at one time, gradually. Also, your usual daily sadhanas can become shorter. Once you are starting to progress, do more and more shi-nä.
During the Vajrasattva retreat it is good to do a self-initiation, short or long, every day, also, Lama Yeshe's Vajrasattva Tsog. This is to make your samaya vows pure, as that is the main qualification for attaining shi-nä.
More effort is required at the beginning; otherwise there will be obstacles later. One old student received advice from Gen Jampa Wangdu, then he went to some Hindu sadhus. He studied and debated with Geshe Rabten and was extremely well educated at an intellectual level. Then, somehow during retreat, he came to the conclusion that his gelong vows were an obstacle to attaining shi-nä. It was strange. He understood the detailed points but could not see this most simple one. I think it is karma that decides one’s life, it is not something to do with intelligence. If the obstacle is karma, it can be purified.
Another senior monk went up to the seventh stage, then he felt that he needed more merit and so decided to stop retreat and help his mother sell flowers. He did not continue, but he had much experience.
Then, there was the lady who thought she had overcome subtle excitement. She told me that she could enter meditation at any time. When I was living in Dharamsala she spent one year with Geshe lamrim and in America. Then she had the idea to marry another student and a strong plan to do this developed in her mind. Shi-nä requires a quiet mind and renunciation; if you have a plan with attachment, then you cannot achieve shi-nä. His Holiness told one student to do shi-nä, and she became very upset – this became an obstacle to achieving shi-nä. When seeking advice from your teachers you must have a very good translator. If you are relating your experience, especially detailed points, you will not get the exact answer if the translator cannot understand.
Another method to collect extensive merit to complete shi-nä is to read the Sanghata Sutra, which I have been recommending all the centers to read to collect merit for the Maitreya Project. Read this 500 times. Do it by combining reading with lamrim meditation. In the morning perform Lama Chöpa and meditate on guru devotion. In the next session, meditate on the perfect human rebirth, karma, and meditations of the first scope for 30 minutes to one hour. Then read the sutra for 30 minutes to one hour. In the afternoon, do the same. A little lamrim meditation and then read the sutra for 30–60 minutes. This is mainly to collect merit so that when you actually do shi-nä there will be no obstacles. Also, it will create the cause to have a very enjoyable retreat. When all the conditions are pacified then the actual retreat does not take much time, there will be no heavy obstacles. If you do not do this you can experience lung and other obstacles.
*Note: For more information on overcoming lung and other practice problems, see the Wind Imbalance/Lung and Practice Problems sections of Lama Zopa Rinpoche's Online Advice Book.