Laura, easiest thing to do is create a new layer, fill it with white (or whatever) and then add a stroke through the layer styles. Make sure you set the option to "inside" stroke to get nice crisp corners. Then adjust your fill opacity on that layer to 0%. That will leave the stroke visible and the colored layer will disappear.

I usually give a quick explanation first and can expand if you need it. Let me know if that didn't make enough sense.

Sonya

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