If you’ve spent time using a desktop or mobile digital- imaging application, you’ll be familiar with the concept of layers. Layers allow you to separate an image into different levels that you can then organise, composite, and combine in different ways.

When you create artwork from scratch, it can be difficult to gauge the best way to use layers, because some iPhone and iPad apps limit you to only a couple of layers per image. Here are steps that will help you use the handy layers feature.

Separate the painting by depth  Regardless of the image you’re creating, you’ll probably be able to group together objects that are similar distances from the viewer. For example, you can separate a painting into two layers – one for the background and the other for a person. A complex composition may have more layers. Distributing parts of the image onto layers enables you to make edits that won’t affect the entire image.

Use as few layers as possible When you use too many layers, remembering the content of each layer gets hard, especially since many iPad apps don’t let you label layers. It’s also easy to forget which layer you’re working on, and switching between layers is time-consuming.

In a complex composition, you may have sky on a background layer, buildings on a second layer, and a person in the foreground on a third layer

Think about your process Consider using layers to aid your artistic process. In a comic book, for example, you could use one layer for a pencil sketch, a second layer for inking outlines, and a third layer to colour in the artwork. Layers are a good way to prevent certain areas of your work from blending into others.

Duplicate and transform layers Most apps let you duplicate, move, rotate, and resize layers. So if you were painting a blue sky, you could easily duplicate and transform multiple cloud layers.

Experiment on a blank layer  As you approach the end of creating a piece of art, you can become anxious that you may go too far in adding finishing touches. We recommend making final changes on a blank layer – if you make a mistake, delete the layer or erase the parts that don’t work.

Merge layers It makes sense to merge layers when parts of the image no longer need to be separate. If you have created a character using a couple of layers for different parts, simplify the art by merging these layers together.

Export layers In some of the iPad art apps, you can export the final artwork as a Photoshop Document (.psd) file containing the original layers created in the app. This is useful if you want to keep working on the artwork in your desktop application.