Photo editing programs such as Adobe Photoshop are not qualified to make a cut-out. Cutting lines
shaped rectangular or square will be generated automatically based on the by you specified sizes.
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"To start, create a closed line in the desired shape without a fill color. In the case of a cutting path with cutout, this should be an entirely closed path. Use the Pathfinder Minus Front tool for this. Overlay the two shapes, select both, and click on Minus Front."
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Next you open the Swatches window. Inhere you turn the line into a spot colour. Create a new swatch.
Name the swatch Cut, turn it into a spot colour as 100% Magenta. Click OK to apply. The line will not be
printed.