here is a way to give your paint a more natural look...
make sure your paint layer is selected....in the layer stack right click your paint layer and create a NEW layer..a window opens make sure "transparent" is selected.(you should name your layers to stop confusion later on)
name the new layer something like "paint_fading_1"
select your paint layer..... using the selection tool select all the base color paint....
(a tip...when you use the selection tool if you hold left click and drag you can change the amount of selection)
select your new layer that you just made...(the selection you made works on any layer that is selected)
go to "Filters" (hint-you can just right click the large window to get to all the options on top of window.... where Filters is) then go to
"Render" go to "clouds" go to "plasma" a window opens......... the more "turbulence you pick the more Mottled it will look....so this layer choose a small amount of "turbulence" click "OK"
a rainbow of colors appear....go to "Colors" then "desaturate" not really important what you choose here..."lightness-Luminosity-Average"click them all..... choose one that you like...click OK
now on the right side where the layer stack is there is a drop down arrow called "Mode" go through each one to see what it does to change the paint underneath
for this I personally like "hard light" and then bring down the opacity to around 40 %
again just the steps are whats important...experimenting is where you find some great effects.....
do this again with a new layer but this time use a lot of turbulence when making the Plasma clouds...
things to rememberthe proper layer is selected
if you are trying to do something but its not working a good chance is you selected something and never deselected...once you select an area whatever you do will ONLY effect the selected area.
Control Z is UNDO very IMPORTANT

in preferences you can change the amount of "UNDO's" allowed the more the better.
hope this helps a bit
