How To Make Multiple Layers Visible In Photoshop. It’s the exact same with any other panel in photoshop. Hit ctrl+t and type 90 into the rotate box in the top toolbar and click the checkmark to commit the transformation.
Ensure both layers are unlocked and visible. Frame 1 will have layer 1 and layer 361 visible. So since you'll most likely want the merged copy to appear above your existing layers, start by selecting the top layer in the layers panel:
