Concentration increases by curtailing your wants and desires, by observing Mouna for
two hours daily, by remaining in seclusion in a quiet room for one or two hours daily, by
practicing Pranayam, by prayer, by increasing the number of sittings in meditation in the evening
and at night, by Vichar, etc.

From „May I answer that“ by Swami Sivananda (1987-1963). More Informations on… http://bit.ly/bOfnig