A guided meditation:

Sri Swami Vishwananda: I would like to do a little meditation with you-a very simple one.

Take a few deep breaths and when you breath out, drop your shoulders; release all the pressure from your shoulders. Close your eyes. Focus your concentration on your third eye. And then, with the power of creation that God has given you, create the OM sign or any Divine symbol or aspect - the cross or any symbol you feel close with. And concentrate all your attention on this point, on this aspect. The mind will think; let it think. Don’t try to stop it; don’t use force to stop it. But don’t hang onto this thought. In the same way it comes let it go. Focus on this Divine aspect, and, with your ears, listen to your breathing. Listen to it carefully. You will hear, when you inhale - if you listen properly - you will be inhaling OM in and the same when you exhale, the sound will be OM. After some time, you will feel a pressure point where you are concentrating. Let it expand. Let this energy expand, covering your whole head. Let it expand to your upper part of your body - your arms, your chest, and your back. Let it expand to the upper part of your body - your legs, your feet. If you have any pain or illness, focus on that point. Let it vibrate. Now, focus on the heart. Let the OM vibrate in your heart. Let it vibrate more and more At the same time, choose the image that you created, that you like, and make it go inside your heart. So come back to yourself.

You see this form of visualisation is very simple for practicing anywhere you are. In place of thinking or talking of things, which are of no use, learn to sit quietly, keep the mind busy, but keep the mind focusing on positivity.