Adjust the orange tones of the uppermost sky layer by selecting Image > Adjust > Replace Colour. Use the colour picker to select the orange tones, and adjust the saturation to -82. Next, hit Cmd/Ctrl + B to access the Color Balance dialog box; reduce the midtone red by -18 and increase the blue by +32.
Disable the visibility of the buildings, target the top sky layer and hit Cmd/Ctrl + Alt/Opt + Shift + E (this copies the visible elements to a new layer; see the Tip on the right). This will be refracted into the sphere later; having the original layers intact gives flexibility to redo a merged layer. Open Hand.jpg from the project files and Cmd/Ctrl + Click on the existing path thumbnail to generate a selection, then paste this into your working file at the top of the layer stack and re-size, rotate and position as shown. Adjust the midtone levels slider to 0.87.
Draw a circle with the Marquee tool, expand or contract the selection and nudge to fit snugly within the hand. Create a new channel and, with your foreground colour set to black, hit Delete, filling with white. Next, with the top composite RGB channel visible, draw a closed path around the little finger, and make a path-based selection. Now target the hand layer and hit Cmd/Ctrl + J to float a new layer; name it accordingly.