In this tutorial, I will be telling you how to make either an image or text look like it's being reflected.
I'm going to be doing text. Shall we start?
1. Make a blank white image, about the size of a header, width of 730, height of 140, for example. (You can add a background if you want, if you want it fancy)
2. Pick a cool text that you really like, and write whatever you want on the scratch image.
3. (Optional, to make outline around text) Open your layers dialog, and right click on your text layer. Go down the box almost all the way until you find "Alpha to Selection." Click that. You will now see a selection outlining the text you wrote. Go to Select>>Grow and change it to 3 or 4 pixels. Create a new layer and name it textbg. Turn off your text layer and drag textbg under it. Fill textbg with any color you want. Turn the text layer back on to see the result. If you like it, right click your text layer and click Merge Down. You can now move the textbg layer wherever you like, and the text won't be left in the old spot.
4. Go to Select>>None.
5. Right click your bgtext or your text layer and select duplicate layer. You will now have two of the text with the background.
6. Click the move tool in the main GIMP window.
7. Move either of the layers you just made below the other one.
8. Flip the bottom one over by selecting the flip tool and clicking the vertical radio.
9. Back to the layers dialog, right click the layer of the text that is below the other. Find add layer mask. The radio should automatically be on full opacity. Change it to black (full transparency.) Press enter.
10. Change your foreground color to white, and go to gradients. Select the gradient that says, "FG to Transparency."
11. Now, go to your image. Make sure the layer below is selected. Hold CTRL, so your gradient will be straight. Now, go from the very top of the area you created, and click. Drag down about 3/4 down to the bottom. Look like a reflection? It should!
Here is mine: