[header] How to begin using the pen tool in gimp [title] Create a new image that is 500 pixels high and 500 pixels wide. [step] Fill with a gradient color of your choice. The example uses a normal red to dark red radial gradient. 
[title] Select your path tool and create a line from the top of the canvas to the bottom. [step] However, leave about 150 pixels of room above the top pen tool mark.