Cloud Sig.. Gradient Map?

Hey i have just finished this sig, and was experimenting with Gradient Maps.
I had a question, when using a gradient map on a layer does it only apply to that layer? or everything? (sorry if this is dumb.. but some of you guys do it and it looks awesome).. and sorry if i posted in the wrong Thread

http://i498.photobucket.com/albums/r...ntyX/cloud.png

Also, tips on how to improve would be great :)

it is only going to apply to the layer selected, just do it to one of the first layers to get it on everything.

A gradient map applies to all layers below it. You can apply it to only one layer by right clicking he gradient map in the layers tab and clicking merge down.
This is for Photoshop. I am unsure whether you can do it the same way in GIMP

Awesome thanks :)