This is one of my first tutorials i made and i'm sharing it with your guys so here it is.

1) Open up your GIMP, and get out your canvas. Make sure the background is white. I used a 400x125, but you can have yours different.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/BlankCanvas.jpg[/img]

2) Now make a new layer, name it C4D Layer. Get out your C4D, copy and paste it to the new layer. Hide the layer. Here's the C4D that I'm using.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/C4Dlayer-1.jpg[/img]

3) Duplicate your white canvas layer, and open your Brush dialog. Now get out a brush of your choosing, and choose the Paintbrush function under Tools-->Paint. Do a bit of brushing, but not too much, so there's still some white showing. Hide this layer. Here's what my brushing layer looks like.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Wabstract12brushing.jpg[/img]

4) Open up your crop image, scale it to your liking, and copy and paste. If you feel the need to rotate your crop, that's fine. Now, go under your Layers dialog, and click on the New Layer icon. This should put your crop on a transparent layer. Then go under Layers on the menu bar at the top of GIMP, and choose Layer to Image size. This should now make a clean, neat layer for you.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/SantaGirlcrop.jpg[/img]

5) Now duplicate your crop layer, and name it Smudge. Go into your Brush dialog, and choose a few brushes that you like. Now smudge outward, making sure you fill the canvas. This is to spread color for your background. Make sure the rate is on 100, so you can see it.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Smudge-1.jpg[/img]

6) Duplicate your smudge layer three times, so there are four smudge layers.
A) Go under Filters-->Artistic-->GIMPressionist, and choose the Ballpark setting. Click Apply, then OK it. Now bring this layer underneath the original Smudge layer, and hide it. Remember to name the layer 'Ballpark' so you know which layer you're working on. This is what the ballpark layer should look like, or something similar to this.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Ballpark.jpg[/img]

B) Un-hide the second duplicated smudge layer. Now go under Filters-->Artistic, and choose Cubism. Leave the settings at default. Name the layer 'Cubism', and bring this layer underneath your Smudge layer. Hide it. This is what your Cubism should look like, or at least something similar.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Cubism.jpg[/img]

C) Un-hide the third duplicated smudge layer. Again, go under Filters-->Artistic-->GIMPressionist. This time, choose Painted Rock. Click Apply, then OK it. Now bring this layer underneath the original Smudge layer, and hide it. Remember to name the layer 'Painted Rock'. This is what the Painted Rock layer should look like, or something similar.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/PaintedRock.jpg[/img]

7) Duplicate your white canvas layer again, and this time open your Patterns dialog. Choose a pattern that you like. Now go under Edit, and choose 'Fill with Pattern'. You should now have a layer filled with a pattern. Name the layer to whatever pattern you chose. Now bring the layer up so it's underneath the original Smudge layer, and hide it.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Qbert.jpg[/img]

8) Copy visible and paste a new layer. Now get out a soft brush (Circle Fuzzy fits the bill perfectly), and choose the Eraser function under Tools-->Paint. Next, name your pasted layer 'Displace with C4D.' Go under Filters-->Map-->Displace. If you're using GIMP 2.4, make sure the mode is on Cartesian. Now choose these for your settings: X (-3), Y (30). Make sure that the Edge Behavior is set to whatever you think looks best. In this case, Wrap looks better, so we're going to use that. Hit OK. Now go to your crop layer, alpha to selection it, make the Displace with C4D layer active. Go under Select-->Feather, and choose a healthy amount. In my case, I chose 50. Click OK, then hit Delete to clear. If there are any unwanted parts, erase them with the soft brush. Set the layer to Darken only at full (100%) opacity.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/DisplacewithC4D-1.jpg[/img]

9) Repeat step 8, except with the brushing layer, and choose these settings for the displacement: X (10), Y (-10). Make sure that the Edge Behavior is set to what you think looks best. In my case, Smear looks better. Hit OK. Go back to your crop layer, alpha to selection it, then make the Displace with Brushing layer active. Feather it again, then hit Delete to clear. Set the layer to Multiply at half (50%) opacity. Go ahead and delete your original C4D and Brushing layers at this time.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/DisplacewithBrushing.jpg[/img]

10) Repeat step 8, this time with the Ballpark layer, and choose these settings for the displacement: X (20), Y (20). Make sure that the Edge Behavior is set to what you think looks best. Hit OK. Go back to your crop layer, alpha to selection it, make the Displace with Ballpark layer active. Feather it again, then hit Delete to clear. Set the layer to Lighten Only at full opacity.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/DisplacewithBallpark-1.jpg[/img]

11) Repeat step 8 again, this time with the Cubism layer, and choose these settings for the displacement: X (-15), Y (15). Make sure that the Edge behavior is set to what you think looks best. Hit OK. Repeat the feathering and clearing as in steps 8, 9, and 10, and this time set the layer on Multiply at 25% opacity.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/DisplacewithCubism-1.jpg[/img]

12) Okay, two more displacings to go. Copy visible and paste a new layer. Now go under Filters-->Map-->Displace, and keep the settings the same as with the last displaced layer. Hit OK. Go back to your crop layer, alpha to selection it, make the Displace with Painted Rock layer active. Feather it, and hit Delete to clear. Set the layer to Darken only at 75% opacity. Do another copy visible and paste, and go under Filters-->Map-->Displace again. This time select the dropdown to your pattern layer. Set the X to 50, and the Y to 50. Hit OK. Go back to your crop layer, alpha to selection it. Make the Displace with Pattern layer active, feather it, and hit Delete to clear. Now it looks just a bit grainy, so let's fix that. Go under Filters-->Blur-->Gaussian Blur. Set the amount to 2. Hit OK. Set this layer on Screen at 30% opacity.
This is what the Displace with Painted Rock should look like
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/DisplacewithPaintedRock.jpg[/img]

and this is what the Displace with Pattern layer should look like.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/DisplacewithQbert.jpg[/img]

13) We're going to do a bit of coloring now. Copy visible and paste a new layer. Now open your Gradient dialog. Choose any three gradients you'd like, as long as they coordinate together. I'm using Deep Sea, Fuchsia 3, and Incandescent. Go under Colors-->Map-->Gradient Map. Now set the first gradient coloring layer to Screen at half opacity. Repeat this step, this time using a second gradient map. This time set the layer on Screen at 40% opacity. Repeat this step again, using a third gradient map. This time set the layer on Overlay at half opacity.
Here is what your three gradient map layers should look like:
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Deepsea-1.jpg[/img]

[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Fuchsia3.jpg[/img]

[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/Incandescent.jpg[/img]

14) Okay, here are the finishing touches. From here we're going to add a border, and optional text. Go back to your crop, and pick out a suitable color with the Color Picker tool. Now go back to your project, and make a new layer from there. Fill it with your chosen foreground color. Now go under Select, and select All-->Shrink. Set it to one pixel, and make sure the Shrink to Image Border box is checked. Now clear the remainder and dismiss the selection (Select-->None). Now go to your main GIMP toolbox, and select the Text tool. A basic font from your computer should be sufficient enough to use. Use the same color that you did for your border, and type in your text on the image. Go to the Move tool under the Transform section, and use that to move your text where there's the most space on your image. Now go under Layers, and choose Layer to Image size.

There, now we're done with the tutorial. Here's my finished product.
[img]https://i214.photobucke*****m/albums/cc290/SilverDivaStrike/Tutorial%20Pieces/SantaDogGirl.jpg[/img]