Can't combine pictures.

I'm new to Photoshop. I'm trying to combine pictures. Only one layer looks like a picture; all others look like checkerboards. Anyone know what I'm doing wrong? Thank you!

In Editor, go to the expert tab.

1. Open picture B, the one you wish to select something from to add to another picture.
2. Use one of the selection tools, e.g. selection brush, lasso tool, to select the object. You will see an outline ("marching ants") once the selection is complete
3. Go to Edit menu>copy to copy the selection to the clipboard
4. Open picture A, then go to Edit>paste
5. Use the move tool to position object from picture B.
6. In the layers palette you should see picture A as the background layer, and object B on a separate layer.

Note: The checkerboard pattern that you reference denotes transparency and will not print.