From FreeCAD Documentation
- Select a View.
- There are several ways to invoke the tool:
- Press the Add Leaderline to View button.
- Select the TechDraw → Add Lines → Add Leaderline to View option from the menu.
- A task panel opens.
- Press the Pick points button.
- Pick the first point on the page to define the start point of the line.
- Pick the next point on the page. Hold down Ctrl to snap to multiples of 22.5° angles. Optionally use a double-click instead of a single-click to finish entering points.
- Optionally add more points.
- If you have not double-clicked a point: press the Save Points button.
- Optionally change the Start Symbol, End Symbol, Color, Width and Style of the leader. See Properties for more information.
- Press the OK button.