Well, i don't know much, but one thing I use, is effects quite a lot (perhaps too much)
If you want tips i suggest pm KEYOGI
(answer away m8

)
Don't try and make a map 1st, spend a couple of hours tracing round things, practice drawing different mountains with each tool.
MOST IMPORTANTLY:
Learn exactly what every tool does, (not just on the toolbar, change all the tool properties) spend, at least a day, seeing if you can draw round a country and make it look different, old/futuristic/modern/simplistic. Until you know your way around photshop/fireworks... whatever DTP program you use.
One other thing, in your source file, keep all layers
Very Organized !!!
(never ever flatten anything, unless it's behaving oddly, i tend to keep a lot of the layers I've flattened in a different file)
I suggest before you make a map, make a little sig or something, with your name in.. your country/flag.... don't just dive in, it never works, with my korea map halfway through, i decided the way I'd constructed everything did not allow nearly enough editing afterwards.
I don't know how you want to make your map, but I usually start with a background, then draw each continent seperately, then put borders in over the top of that.
basically just have fun trying out different things, you won't finish it if you don't find all of it fun (bar army centering that is

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