The Double Exposure layer is an represents an image from a photo or other image file. Parts of the image may be erased with the brush tools. The image can be moved, resized, or rotated. A new Double Exposure layer can be created by clicking the Double Exposure effect inside of the More Effects dropdown in the Effects tab of the toolbar.
Choose Image Eraser Tools
Click on the Choose Image... button to open the file browser and choose the image to be used for the double exposure effect. Size
The double exposure image size can also be changed by dragging the image's scale handles on the canvas viewer when the image layer is selected. Rotation
The double exposure image can be rotated using the canvas widget's rotate handle. Opacity
Use the Opacity: slider to adjust the transparency of the overlay image.
The Eraser Tools button will let you use the brush tools to draw-in and erase-out where the effect is applied. Image Effects
An effect can be applied to the overlay image by checking the Use Effects checkbox.
Use the Choose an Effect pulldown list to select the effect to be applied.