Backgrounds can make or break a banner ad or brochure panel, so creating exciting backgrounds that engage a potential customer is very important. Organic designs like that of a stained glass window can work in many different settings. This tutorial walks you through how to create a grungy, stained glass look that you can easily adjust later to meet the color scheme of any design. 
1. Start with a new document. Ours will be 400px by 400px for this tutorial, so you may have to adjust some settings to get the same effect if you are using a larger canvas size.

2. Paint a solid black background on your background layer and duplicate the layer three more times. Use the Layer -> Duplicate layer to speed up this process. We renamed our layers for this tutorial:

 
3. Make sure you the default colors are set by clicking on the reset button:

 
4. With your top layer (our “Layer 4”) selected, go to Filter -> Render -> Difference Clouds. Press Ctrl + F three times to create a strong contrast.

 
5. Go to each of the other three layers and repeat the Ctrl + F step three times on each layer.

 
6. On the bottom layer (“Layer 1”), go to Filter -> Texture -> Stained Glass and use the following settings:

 
7. On “Layer 2,” go to Filter -> Texture -> Stained Glass and use these settings:

 
8. “Layer 3” gets these settings:

 
9. And “Layer 4” is this:

 
10. Now, change the top two layers’ (layers 4 and 3) blending modes to Multiply with an Opacity of 50%:

 
11. Change the “Layer 2” blending mode to Screen with an Opacity of 75%:

 
12. Now you can add depth with color by going to the Image -> Adjustment -> Hue/Saturation menu for each of the layers. Check the colorize box and change up the Hue setting for each layer to create depth or keep the Hue the same and just use different Saturation levels to create a pattern of analogous colors:

 
You can change the order of the layers, add a new layer with its own pattern, and change blending options to quickly come up with new designs and ideas. Change up the settings you go to come up with your unique look. In our final comp we added another layer on top with Stained Glass settings of 2, 1, and 10; we changed the blending mode to Overlay, dropped the Opacity to 50%, and changed the Hue/Saturation to give our image all the more depth and tone.

You can easily create and print posters and banners with these backgrounds, too. Just use your Crop Tool to grab a small section of the design, crop down to size, and make any minor adjustments you want.