More than 10,000 people have already signed a special birthday card for Pope Francis.

You can be among the thousands more expected to sign the card and pledge a simple gift for the Holy Father.

Francis celebrates his 77th birthday on Dec. 17, and this four-foot-tall birthday card will be shipped to the Vatican and presented to him in time for his special day.

This card features a large depiction of “Mary, Undoer of Knots,” a painting done in 1700 that moved a priest named Jorge Mario Bergoglio (now the Pope) when he saw it.

Father Bergoglio brought the image to his native Argentina and expanded it into a devotion in the 1980s. He even composed a prayer to Our Lady under the title. From there, the Marian devotion has spread internationally.

This oversize birthday card is the brainchild of Mark Nelson, the founder of Catholic to the Max, a Catholic company based in Steubenville, Ohio, that reaches out to youth and evangelizes with many of its products.

In November, the company took the giant card to the National Catholic Youth Conference in Indianapolis. There, more than 10,000 teenagers from across America signed it.

But there’s no age limit on signers.

If you are near Steubenville, you can sign in person at various locations like area churches and Franciscan University.

But digital signing is available on the website, so anybody, from Walla Walla, Wash., to Bethlehem, Conn., can put their John or Johnette Hancock on the card.

Along with wishing the Holy Father a "Happy Birthday," signers can give a gift, too.

There are suggestions on the signing site for the faithful to choose from. They include: I offered Mass for you, I prayed a Rosary for you, I served the poor on your behalf, I offer my holy Communion for you, I prayed an Our Father for you, and so on. There is also a blank space to fill in some other gift.

Nelson said of the gift idea, “We wanted to give the Pope a gift he would truly appreciate; something he would be proud of. From day one, he has asked all of us to pray for him and to serve the poor. This is our response.”

Digital signatures and gift options will be printed out and attached to the card, along with all the sheets of signatures done in person.

Make sure to sign any day from now until the card is shipped, Dec. 9, so that it arrives in Rome for the Pope’s birthday.