To measure the width of aluminum strips, you can use a digital caliper or a micrometer, which are precise measuring tools. Place the strip between the jaws of the caliper and ensure it is aligned with the jaws' edges. Take the measurement at the widest point of the strip. If a caliper isn't available, you can use a ruler or tape measure, but this may be less accurate. For consistent measurements, measure the strip at multiple points to account for any variations in width.