M. To set up the drawing environment

The scope of the section is determined by first setting the overall dimensions of the workspace to extend to (at least) the maximum dimensions of the section that is to be considered. A grid is then placed within this workspace, which if selected in the options, can be snapped to in order to accurately locate the coordinates of the boundary nodes.

Select either:

Edit > Overall dimensions

or
the Overall dimensions tool

The Overall dimensions dialog opens
Type the maximum width and height of your section.
Tip: This can be edited later by repeating this procedure.
Click OK. The section axis is displayed.
To set up a grid, do the following:
1. Select either:
  
  Settings > Grid options
  
  or
  the Grid step tool
  
  The Grid parameters dialog opens.
2. Type the Y and Z direction grid increments.
3. (Optional) Type an Angle used to orient the grid. The angle is measured positive counter-clockwise from the Y axis.
4. Click OK.
To display the grid, select either:

Settings > Grid

or
the Grid tool

The grid is displayed and the tool is depressed on the toolbar and in the menu.
To snap points to the grid, select Settings > Snap to grid.
Note: This tool is on by default when the grid is displayed.