Ill draw a picture for you and explain it, click on pictures because they are to small to just look at


[align=center]a plant at a young age looks something like THIS

[attachment=o206970]





You tie the top part down gently something like THIS


[attachment=o206971][/align]









Then those little leaves you see coming out grow up to be side branches resulting in a bushiness visual, adding more bud spots in a vertical restriction and also resulting in an even canopy and more main colas like THIS


[align=center][attachment=o206972][/align]



Hope this helps, tell me if you need more explanations


Sorry for hijack