It is very easy to create a realistic paper texture from scratch in Photoshop. For this we will be using several filters and effects.
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Necessary
Adobe Photoshop program
Instructions
Step 1
Create a new document at 1280 x 1024 px. Make a rectangular selection in the center of the canvas and press Q to switch to Quick Mask mode. Go to Filter> Pixelate> Crystallize, select a small cell size and click OK. Press Q again to return to normal mode. Create a new layer, press D and then Ctrl + Delete to fill the selection with white. To deselect, press Ctrl + D.
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Step 2
Select the Burn Tool with an exposure of 20% and drag across the canvas until it looks slightly dark and muddy. Go to Filter> Texture> Texturizer, select the Canvas texture and click OK.
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Step 3
Double click on the "paper" layer to open the layer styles. Turn on the Drop Shadow effect and click OK.
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Step 4
In the Layers panel, right-click on the Drop Shadow effect and select Crete Layer to separate the shadow from the "paper".
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Step 5
Select the shadow layer, press the key combination Ctrl + T to transform, right-click on it and select Warp. Move the handles until the shadow looks realistic.
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Step 6
Select the Gradient Tool, in the Options Bar, select Linear and the Difference Mode. Create multiple arbitrary gradients in different directions - top to bottom, bottom to top, left to right, right to left, etc.
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Step 7
Go to Filter> Stylize> Emboss. Press Ctrl + L and move the black and white sliders to the center.
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Step 8
Press Ctrl + Alt + G. Change the blending mode to Overlay.