The Three Centers Standing Method:

Master Luke Chan: One of the high standards of meditation is to become "nothingness": you focus on nothing, your body becomes nothing, and yet you become everything. There are immediate stages to reach to such a high level skill. One stage is to focus on one thing within your Dantien area. This is known as "one thought replaces ten thousand thoughts". To focus on one thing, you need to stabilize your body in such a way to make you feel restful and comfortable. One good  image you can use to do that  is to become a tree as Giuliano points out in the following article.


The Standing Method
Doing the Standing Method can help you become more centred. You have to become rooted and have roots like a tree. Become the tree. And in a way if you can stand still and be focused for forty minutes you will have greater mind power to do any other exercises. In the past my mind would begin to wander off after 15 minutes, but by focusing on your Dantien area and the roots going down into the ground it becomes a lot easier.
Giuliano Neri