1) place you feet next to eachother and make a step of normal length with your center of gravity (your hips) between your feet.
2) Bend the knee of your front leg and have your upper body and back leg in a straigth line. Keep the heel of your back foot on the ground. DOn't push an against a wall;-)
If you need support try to grab something on your side so you use it just for that: balance.
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Hold this position for at least eight seconds. Than come back to the starting position and repeat the motion with the other leg. In video it looks like this (thanks to the Asics site):
id='kuiten_bstr'
codebase='http://activex.microsoft.com/activex/controls/mplayer/en/nsmp2inf.cab#Version=7,0,0,1954'
standby='Loading...' width='240' height='180' >
name='kuiten_bstr'
title="Zijaanzicht - Kuiten (gestrekt)"
pluginspage='http://www.microsoft.com/Windows/MediaPlayer/'
type='application/x-wmplayer'
loop='true'
cache='true'
controller='false'
showcontrols='false'
autostart='true'
autoplay='true'>