Premanand Maharaj Ji
How can I practise quiet mantra meditation in daily life?
One quiet hour with your mantra
Out of 24 hours, take one hour in solitude and think only of your mantra, with no effort and no other thought. If you do this, your inward-turned nature (antarmukhta) begins to grow.
Sit quietly and think only of the mantra, calm and turned inward, where no noise or talk from outside is heard; find such a time, find it at night.