Inverting your images is a handy way to turn your images from black pencil sketches into a white-pen or "chalklike" pencil form. They'll help to make the concepts and the ideas you are trying to convey easier for your audience to understand. All you need to do is have your image(s) ready, and Photoshop (I'm using CS4, but this should work for any version of Photoshop).
Let's start!
So here's the image I am going to start with:
And here's the result (granted, the result of this picture has a lot of extra lines in it, but this is the folly of using standard notebook paper for sketching!):
So the first thing you need to do is open your image into Photoshop Then go to Select > All (CTRL/Apple + A).
Then the "marching ants" or "marquis lines" should appear around your image.
Next, go to Image > Adjustments > Invert. This can also be done by using CTRL/Apple + I. This will "flip" all of the colors in your image.
And then you're done! Make sure if you want to do anything else with your image you either deselect (CTRL/Apple + D) and/or save your work.
