These sand dune watercolor greeting cards are a great way to send your heartfelt messages. To use them, simply write your personal note inside the card and seal it in an envelope. For best results, use a pen or marker that won't bleed through the cardstock. When storing the cards, keep them in a dry place away from direct sunlight to prevent fading. If the cards get dirty, you can gently wipe them with a soft, dry cloth. Enjoy using these lovely cards to brighten someone's day!