Go to the Dashboard page by clicking on "Dashboard" in the sidebar navigation.
Toggle to "Edit mode" to the right side of the second navigation bar.
Select the farm in which the block is by clicking on the farm on the map.
Click on the sign on the left of the map.
Click on the button of "Boundary" and make sure that the drawing tools is visible on the right side of the map. Select the "Polygon".
Click on the map for each point on the boundary to draw the boundary line. The last point should be joined with the first point.
You can edit the boundary by clicking and dragging points around.