The board should be mounted flush to the wall and not leaning at all. The 20 should be at the top.
It is also advisable to have a raised oche. If your oche is flush with the floor it is all too easy to place your foot or toes over the line without noticing.
Distance to the toe line
When measuring the distance to the toe line it is important to make sure you measure from the bull and not the wall. If you choose to measure from the wall you must ensure you have compensated for the thickness of the board. I find it easier to use the diagonal measurement 2.93m.
I’m a paragraph. Drag me to add paragraph to your block, write your own text and edit me.