Meditation while in a sitting posture is the most beneficial. To sit, find a comfortable chair or use a comfortable cushion to sit on the floor while someone is guiding you. Sit with your back erect, balancing your head effortlessly. Let your arms relax at your sides, with your hands resting open on your knees. Yoni Mudra, also a sitting posture is an guided meditation for healing exercise in Pratyahara or withdrawal of the senses. One must try to block off your ears, eyes, nose and mouth you retreat inside yourself like a tortoise drawing its legs under its shell. You will notice that slowly your senses are brought under control and the mind is no longer pulled constantly outward, now you can  hope to concentrate.