For roller shades that are 4 to 6 feet long, including your 63-inch shade, it is recommended to use at least three mounting clips to provide proper support and avoid damage. Since you received only two clips per shade, you should acquire additional clips to ensure even weight distribution and stability. Avoid placing clips at the extreme edges; instead, position them toward the middle for better support. If you need, we can assist in providing the correct extra mounting clips to complete your installation securely.