overlay a texture?

maybe look on here?

http://www.threadless.com/profile/115982/Manos/blog/304635/Get_your_T_SHIRT_TEXTURES_here

1. find a texture on a website (here's a good site to use!)

2. download the largest one you can (if it's small, that's fine, too, you can always copy+paste a few times and make like a quilt of the texture

3. open the picture in photoshop

4. convert to greyscale (image-mode-greyscale)

5. open up Levels. (image-adjustments-levels)
this option lets you modify how much white/black/grey is in the image. the amount of contrast and these three colors, in the current configuration, creates what appears to be the texture. we don't want that, though, we just want something that resembles distress!

7. we're interested in the Input option. slide the black and white sliders as close as you can together. this eliminates the grey and makes it a black and white image.

depending on how for left or right you bring the sliders determines how much of the image is left black, and how much white. we'll end up deleting the white space and making it where the design is, so most of the space should be white (you'll learn this as you play around with adding distress for the first time).

usually, sliding them together almost all the way to the left produces what you want.

8. once you have what you want, convert the image back to RBG or CMYK. (image-mode)

9. Select the white area (Select-color range, then click white on the image), and delete it (once it is selected, hit Backspace)

10. Select the black area (easily done by going to Select-Inverse). Copy it.

11. Paste it on top of your design

12. this is the step im still trying to figure out. i know you're supposed to use a blending option, like multiply, to make it 'delete' the part of the design below it. but usually i just make the distress the same color as the shirt/background and that looks fine!

(to fill the distress layer, once its copied, ctrl+click on the little preview of the layer under Layers. this selects everything on the layer. Hold ALT and go to Solid Color under Layer Adjustments (the half-black/half-white circle icon). then with the box open, you can click the color of the background and voila!

if your distress is too small/too thick in certain areas, its pretty easy to modify. either delete it once you paste it, or go back to the original and delete stuff there.

i hope that helps!