To start a new image, click "File" -> "New" on the user menu.
This is used to set the name, size, and color of an image. The size can be chosen arbitrarily or from the templates. New sizes can be added to the templates as well.
If there is an image in the clipboard at the moment, the size of that image is used by default.
This is used to create an icon.
The name and size of a new icon, as well as the color intensity, can be set here.