Tutorial: Generate a stripe-like texture
Open up a new file: 500×500px.
Add a new empty layer.
Choose Filter / Render / Clouds / Solid noise.
Choose the values shown in the picture below:
(x:0.1, y:16, random)
Go to: Layer / Rotate Layer or just press SHIFT+R. Rotate it for 25°
Choose the crop tool, adjust it to a certain part of the picture so that everything inside the selection is covered by the texture. Press ENTER.
Optional: Filter / Enhance / Sharpen if you want to see more detail in your texture.
Now choose (in GIMP 2.2: Layer /) Colors / Colorize.
Move the brightness up a bit and take a color of your choice! I’ve taken a soft blue.