How to draw a polygon

Select the polygon tool from the tool bar. Click the left mouse button where you want the first node of the polygon. Without releasing the button, drag the mouse to the point where you want the second node, then release the button. Click the left mouse button where you want the next node and release the button. Click and release the left mouse button where you want the next node, and the next, and so on. When you come to the last node, double click the left mouse button.

To draw a closed polygon, double click on the first node, as the last node.

How to add or delete nodes from an existing polygon

You can insert nodes, delete nodes, or close or open a polygon using the context menu. To insert a node first select the polygon. Make sure the selection tool is selected on the tool bar. Then using the right mouse button, click on the polygon where you want to insert a node. A context menu will appear. Choose Insert Node from the context menu.

You can delete a node by clicking the right mouse button on the node you want to delete and then choosing Delete Node from the context menu.

How to close an open polygon

You can close or open a polygon by choosing Close from the context menu.