You should use a graphics package to create, edit and save images for a DiDA project. Graphics packages are good for working with layers and adding effects to an image.
Prior to selecting a graphics package, try out a variety of different ones, and the various tools and techniques available. You may or may not like the different effects available, and you will only find out by experimenting.
The features of most graphics software include:

The features of most graphics packages include: canvas, tools and layers window.
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