If you have a texture that you would like to use as a website background or a texture that isn't quite large enough for the format you're designing for, knowing how to turn that texture into a tileable pattern is extremely useful.
Today, I'm going to show you how using a simple tried and tested technique.
Select the Crop Tool (C), hold Shift and select an area of your texture that you would like to make tileable. Try to avoid any distinctive marks or drastic changes in brightness.
After cropping your image, open the Image Size window (Alt+Cmd+I) and make a note of the dimensions. Then go to Filter > Other > Offset and set both the Horizontal and Vertical offset to exactly half.
Any seams in your texture will now be visible. To remove them, you need to use the Clone Stamp Tool (S).
Once selected, choose a brush with a similar texture to your image. I'm going to use Photoshop's default Rough Round Bristle brush.
Next, you need to set the sampling point, which basically means selecting an area of your texture that you would like to clone. To do this, hold Alt and click.
After setting the sampling point, release the Alt key and use your brush to start painting the sampled area over the top of the seams. It's important to note that you should paint up to the edges of your image but not over them, otherwise your texture might not tile seamlessly.
It's likely that you'll need to set new sampling points during this process, which you can do by simply holding Alt and clicking another area of your texture that you would like to sample.
Once you've finished painting over the seams, press Cmd+F to repeat the Offset filter. This will allow you to check that your texture does tile seamlessly. All being well, there should be no more seams, but if you do see some irregularities, use the Clone Stamp Tool (S) to remove them.
Now that your texture is seamless, it's time to create your pattern. To do this, go to Edit > Define Pattern and enter an appropriate name.
Following that, create a new document (Cmd+N) at least twice the size of your texture. You're going to use this to test your pattern.
Go to the Layers Panel, right click the 'Background' layer and select Layer from Background.
Name this layer 'Texture'.
Now double click the 'Texture' layer to open the Layer Style dialog box.
Click Pattern Overlay and select the pattern you just created.
This will apply your pattern to the layer, allowing you to see how well your texture tiles. Like in my example below, there may be areas of your texture that make it obvious you're using a pattern.
You can go back to your original texture and tidy up these areas using the Clone Stamp Tool (S).
After you've made your refinements, you'll need to define your texture as a pattern once again. Just as you did before, go to Edit > Define Pattern and enter an appropriate name.
Switch over to the document you created to test your pattern, double click the 'Texture' layer to open the Layer Style dialog box, then apply the newest version of your pattern.
The tiling should now be far less noticeable.
If it still needs some work, you can always go back and make some more refinements to your original texture. Just remember to define it as a pattern once you're finished.
How did your pattern turn out? Feel free to share your examples in the comments section below.