Go back to your main art document and make the "Pattern" layer active by clicking on it.

Go to your filters menu and choose "Distort>Displace"

Choose the default setting of 10,10..repeat edge pixels. Click OK and browse to the "Displacement.PSD" document we previously saved. Click OK.

Now your texture is "wrapped" around the folds and curves we shaded. If the effect is too strong..undo the filter and redo it with a lower setting like 5,5 or so.

Use the mask channel we made that doesnt have shading to select the textured area. Invert the selection and trim away the excess pattern.