Delete, edit, add

 When using photoshop, there are three main ways of manipulating images. They are deleting unwanted content, editing content or adding content. This can be done in Adobe Photoshop, Express, InDesign and Illustrator. 

In understanding design, there are 5 elements which dictate this. They are shape, line, mass, color and  texture. Collectively, these are important factors to employ in your work. 

                              Make a Photo Collage in a Matter of Minutes - Grandma Ideas

ADD

CHANGE 

DELETE.

All these aspects of design can be done to create images. 

Finally, don't forget to include wider social context such as political, economics and social.