Make the first print cheap
Print a plain-paper proof before using adhesive stock. Match the paper size and select Actual Size / 100%. Measure the calibration line, then compare the outlines with the label cuts. A light source behind the two sheets makes a consistent position error easier to see.
Keep the manufacturer's model code and a link to its layout source with the stock package. Different products can share a label width while having different pitch or margins. The template finder shows source details when a verified layout is available; otherwise measure the sheet and use the calculator.
Check one sheet before a batch
Use the same tray, feed direction, and print settings for the final stock as you used for the proof. Print one label sheet and inspect the top and bottom rows. A constant shift can be corrected with X/Y offsets, but increasing drift calls for a page-size, scale, or pitch check.
Store the successful PDF and printer settings with the stock details. If the printer, driver, viewer, or paper changes, repeat the proof. A few minutes of measuring is usually cheaper than discovering an alignment error after a full batch.