Padmasana

'Padma' means lotus in Sanskrit language.This asana  resembles lotus.It is one among sitting series of asana.It is mainly for meditation and pranayama practise.In the beginning you may feel difficulty in sitting padmasa for few minutes,but after practise one can sit in padmasana for hours together.
How to practise Padmasana
For any asana practise stomach should be empty.Early morning is preferable.Other wise 3-4 hours after food one can practise.
Room should be well ventilated.Put a mat or bed sheet over clean even floor.
Sit o the mat by spreading the legs forward.
Keep your left foot on right thigh and right foot on left thigh.Place the hands on knee joint. or do Chinmudra.
One has to observe his nose tip.
''vamoru paridakshinam cha charanam samsthapya vamam thatha
Dakshro  pari paschimena vidhina druthva karabhyam drudam
Angushtav hrudaye nidaya chibukam nasagramalokayeth
yethat vyadhi vinashakari yaminam 'Padmasanam"prochyathe''This is the classical reference for Padmasana.
Uses/Benifits of padmasana

1. Opens up the hips
2.  Stretches the ankles and knees
3.  Calms the brain
4.   Increases awareness and attentiveness
5.   Keeps the spine straight
6.    Helps develop good posture
7.    Eases menstrual discomfort and sciatica
8.    Helps keeps joints and ligaments flexible
9.    Stimulates the spine, pelvis, abdomen, and bladder
10.    Restores energy levels

P.S.This is for referance only.One has to practice asanas under the guidance of yoga teacher.