After some experimenting, I came up with this card you can make at home, and send to a loved one. Older children could even make their own cards. Tip to make this easier: pre-punch the holes using an awl tool with something underneath so you don't damage your table. I use a small plastic cutting board, that I just use for crafting.
embroidery floss (2 single strands for each color-or you can use more for a thicker effect)
black scrap paper
adhesive (glue stick or glue dots or mounting squares)
With a pencil draw a dotted line arch.
Carefully stitch each color of the rainbow, starting at the top and working down.
Attach the buttons.
Cut the black paper to form a 1/2 a circle. Attach to card.
Write a message to the recipient about how grateful or lucky you are to have that person in your life :)
Happy St. Patrick's Day!