How do I make my colors have "texture", this kind of label, and land masses?

[Freodin]

In the context menu for the layer (right-click on the little layer icon in the list), you can find the stuff that deals with layer masks. (And a lot of other things, for example the option to add a 'layer group').

To add a layer mask, simply choose "Add layer mask". You will be offered several options to create the initial layer - for starters just use the "white - full opacity" option.

A second layer symbol will now apear to the right of the other one: this is your new layer mask.
You can chose it as the 'active' drawing area just like you chose any other layer: with a left-click. It should now have a white border around the little icon... the main layer should have a black border.

Such a layer mask is always a grey-scale image. Everywhere the image is white, the main layer will be completely shown - where it is black, the main layer will be completely transparent - and grey values give you the corresponding transparency.

You can draw directly into the layer mask, but if you want to apply the same mask to different layers, I found it helpful to create a special layer for the mask.

Create a new layer and fill it with black. Now paint in white the area where you want your picture layer to be shown. You can do that by any means you want or find explained in a tutorial (for example this 'solid noise method' you mentioned in the first post). You can then hide the layer by clicking on the little eye symbol next to the layer icon. This layer is for storage of the mask only... you don't need to see it.

Now copy this layer - CTRL-C will do fine.
Activate the layer mask on your work layer by left-clicking on it. Paste the copied layer - that should be CTRL-V. A new layer will appear on to of your layer list: "Floating selection (Pasted layer)"
Right-click on this layer icon, and choose "anchor layer" from the context menu. This will now paste this layer into the chosen layer mask.


And this is the way I do it. There are other ways, using channels or selections... but I found this one the most intuitive.