A superb tutorial on adding a border to your quilt top by Jo Baner. One of the most common mistakes when adding a border is not measuring. This can create wavy borders and lead to difficulties and puckers when quilting. Another trick for ensuring that your quilt top lays flat after adding the border is to cut the borders from the lengthwise grain of fabric.
Watch this fabulous video which will help beginner quilt makers when it comes to sewing on borders. Pressing and then measuring your quilt top is very important, as is folding the fabric correctly before cutting your borders.
Many easy quilt patterns include an outer border, so learning how to avoid common mistakes will be time well spent.