Need help making a shape

I want to take a picture, and turn it into the shape of our country. Kindof like the one Im posting here. Whats the best way to do this?

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Probably with a vector mask. I don't really know the details, try googling that.

Here you go. Resize this and use it as your mask.

Ok I have the photo, but Im looking at how to actually do this. Im still very new to PS.

The simplest way is to convert your image into a brush

Desaturate your image to make it black & white
Go to Edit > Define Brush Preset and save it as a brush.
Look in the Brush palette and it will be the last brush listed.
just click and it will be selected.