1. How do a black border line on the top and bottom of my signature like others do?
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Use the black brush (look for the square ones that come with the program), You start from top left, hold SHIFT and make your way through to the right, remember this must be on a new layer.. Then duplicate the border's layer, then move that border down to the bottom.. So they are definitely equal.
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2. How my picture stand out without using opacity so much?
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New layer> Apply image> Sharpen. Use photo-filters.

Or.. If you look at my tag in my signature, see how the background is blurred? (3.6 Gaussian blur, duplicated it and set it on overlay 30%). The render is standing out.
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And any other tips that can help me become better ?
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Follow tutorials and learn methods and your tools, mess around with stuff. Use the program constantly and get to know it better.
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