Handwritten thank you letters are nice, and they help boost contributions for nonprofits.

Nearly 70% of U.S. households donate to a nonprofit throughout the year, and statistics suggest that 70% of those generally donate at least once during the holidays. With nearly half of us supporting a nonprofit during this season, fundraisers need to get it right.

The following are a few tips on annual fundraising appeals.

Personalize: With technological advances, we have greater opportunities to connect directly with donors. Your donors should feel valuable to you. You wouldn’t send Aunt Jane a form letter as a thank you note, don’t send your donors anonymous letters. Use first names; be personal.

Also, refer to previous gifts. Not recognizing a gift is like greeting a friend at a party by extending your hand and saying, “Hi, it’s nice to meet you.”

Write by hand: Some studies show that handwritten communication increases the chances of a donation by 300%.

Include stories and numbers: Nonprofit stories are abundant, which is especially true during the holidays. A strong appeal includes stories and numbers. Sandra, a client of the OC Rescue Mission, says “There’s nothing like not knowing where your kids are going to lay their head down tonight.” The Rescue Mission goes on to report serving 3,499 meals in a day. The number takes Sandra’s story and increases the impact a thousand fold.

Never forget to say “thank you:” According to Ahern Communications, one national nonprofit tested the importance of thank you’s by sending some to one set of donors and not sending any to another set. While they received the same number of gifts from both sets, the group that received thank you cards gave $450,000 more than the group that didn’t.

Thank you’s, personalization and numbers all matter. But what matters even more, to borrow Nike’s unforgettable phrase, is to just do it. Go out there and make the ask; make it a happy holiday for one and all.