In the Layers pane we need to right-click on the layer we have coloured blue and select ‘Add Layer Mask’, stick with the default settings and choose a small, soft-edged Paintbrush.

For more fine-tuned blending, you can apply a white layer mask to the top layer using the "Layer" drop-down menu. With a white layer mask, when you paint over the top layer, the bottom layer emerges.

The technique makes use of layers and layer masks in The GIMP, so it is important to have a basic understanding of what these are beforehand. The next section introduces these concepts and provides a ...

GIMP is a free Photoshop alternative that lets you create and edit graphics just like Photoshop. In this video, I'll show you exactly how to use Gimp, step by step. First, I show you how to ...

You can also use the GIMP to export any of its other supported image formats to PDF and the export settings let you maintain any layer masks you used in the original image.