This is the basic standing pose. Tadasana simply implies a pose where the one who practises stands firm and erect as a mountain, with Tada meaning mountain in the term Tadasana and 'Sama' meaning upright, straight and unmoved in the prefix of the term Samasthiti while the suffix Sthiti meaning standing still or steadiness.
1.One is to stand erect with feet together and heels and big toes touching each other. Rest the heads of the metatarsals on the floor stretching the toes flat on the floor.
2.Tighten the knees and pull the knee caps up, then contract the hips and pull up the muscles at the back of the thighs.
3.The stomach is to be kept in , the chest forward , the sine stretched up and the neck straight.
4.The weight of the body should be evenly distributed on both the heels and the toes without bearing the weight individually on the either of them.
5.The arms are supposed to be stretched out over the head in Tadasana but for the sake of convenience they can be placed by the side of the thighs.
Since this is the basic standing pose, the other standing poses can be practised starting with Tadasana with the palms by the side of the thighs.
This asana distributes the body weight evenly on the feet there by aiding in avoiding deformities that hamper spinal elasticity. The hips are contracted, the abdomen is pulled in and the chest is brought forward. The body feels light and mental agility is acquired.
Disclaimer:Before practice, please consult your doctor in case you are suffering from ailments. It is recommended to practice under the guidance of experts.