|Many sewing machines have markings to help you line up your seam allowances, but if your machine is European-made like mine is, the markings are in metric units. I had been eyeballing a 5/8" or 1/2" seam allowance until I realized a simple solution. If your machine has the capability to move the needle to the right or left, use it! Move the needle to the right (or left) until the distance from the needle to one of the lines is 5/8" - or whatever other measurement you need. I put the needle down and use my seam gauge ruler to check the measurement.
This also works great to get a 1/4" seam without needing a special quilting foot. Just move the needle to the right until the distance from needle to the right edge of your presser foot is 1/4".