This should be simple, but cutting out images with rounded rectangular corners in Photoshop is frustratingly difficult when you’re first learning how to use the software. This is how I do it (although I welcome suggestions on making it easier!):
Step 1: Open your image in Photoshop.
Step 2: Select the rounded corner tool:

Step 3: Set the border radius (to determine how curved you’d like your corners to be):

Step 4: Use your cursor to draw the rounded corner rectangle on top of your image:

Step 5: Click on the vector mask shape you’ve created:

Step 6: Now, drag that vector mask onto the layer that contains your image so it looks like this:

Step 7: Click on the layer that contains your image (and the vector mask) so the background of that layer name turns blue:

Step 8: Now, click specifically on the vector mask so that it gets outlined with a small black outline:

Step 9: Right click on your image (where the rounded rectangular outline appears) and select “Make Selection”, then click “OK” when prompted:

Step 10: Hit “CTRL+C” to copy the selection and then “CTRL+V” to paste it as a new layer on your image.
Step 11: Return to your layer palette and turn off all the layers (by clicking on the “eye” symbol) EXCEPT for the layer that you just pasted:

Step 12: You should now have a perfectly beautiful image with rounded corners!

Gingerbread photo by avanzero.
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