one way to make panels or frames.
1 layer 10x8
2nd layer make a rectangle a with a marquee.
to scale the marquee .top center icons 9th icon from left "scale up scale down rotate"
or
if you want a perfect 4x3 make a file/new 4x3 copy n past in the 10x8.
 
to move "move layer" 4th icon down from top. the tool bar on the left.
 

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10x8 inches at 72 dpi is only 720x576 pixels.
that's to small.

 

I'd make sure ya have enough dpi's
 
my skull mask posted as a exsample is 900x900 pixels
the one I'm working on is 6000x6000 pixels.
 
I'd try for at least 3000 pixels

 

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 why are you making it 10x8 ?
 

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I followed a flame tutorial here.some tutorials might help you
ya see on the left.ya half to go "resources n stock images/tutorials"
http://www.deviantart.com/browse/all/resources/tutorials/?q=ms5

 

 

 

 

 

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