Transform Warp Tool

• A very useful tool for creating folded paper effects is the Transform Warp tool. This tool is accessible in the Edit menu. Go to, "Edit," "Transform" and "Warp" to reach the Warp tool. Be sure to first duplicate your layer and place the warped version on top of your original. The Transform Warp tool will allow you to distort the image and give it the illusion of a folded corner or sheet by letting you stretch the image through movable image graph points. The image will distort around these points and can give the illusion of having been folded.
  
  

Polygonal Shapes Tool

• The Polygonal Shapes tool combined with the Marquis Tool lets you select portions of your paper image to create the illusion of folds. Prepare your Photoshop image (such as a magazine cover) and select a shaped portion of your cover design with the marquis. Copy and paste the shape on top of your original layer. Select either triangular shapes for corner folds or rectangular shapes for full page folds, and then use the elliptical shape tool to cut out rounded portions, furthering the illusion of a fold or page curl.
  
  

Gradients Over the Folded Shapes

• The Gradient tool is often applied on top of the folded shapes to create the illusion and shadow of a folded page. Apply the Gradient tool inside the Photoshop Layers Style palette. Set the transparency of the gradient based on the illusion of light hitting your folded page. Setting the Gradient tool to black and white will give depth to your folded paper effect.
  
  

Shadows and Drop Shadows

• Placing shadows using the Dropshadow Layer Style, or creating them by hand, will give further depth to your folded paper effect. Shadows can be placed underneath your folded paper by applying them to the shapes you have cut out. Shadowing can also be applied by shifting the color opacity of two adjoining shapes so that one appears darker than the other, furthering the illusion of a folded paper.