The most important thing about creating a letter box for a loved one is to get started, says Mark Button, who with his wife Diane wrote “The Letter Box: A Story of Enduring Love” (Beyond Words Publishing).

It’s probably easiest to peg your first letter to a particular occasion, to be read now or in the future, the authors say.

“Share your memories of your own past as well as memories that include the person for whom the letter is intended. Children will want to know about things they did and family adventures they may not remember. Parents, friends or mentors will be touched to learn how special they are to you. Be lavish with praise, generous with your heart, but above all, write from a place of love,” advise the Buttons.

If you’re still looking at a blank piece of paper, the Buttons suggest would-be letter writers ask themselves questions, such as:

When was the first time your fell in love? Where did you go on your first date with this person?

What do you remember most about your wedding day?

How did you feel the first time you saw your baby?

How did you spend your most memorable holiday?

Have you ever left anything unsaid that you now regret?

Other practical tips included in their book are:

Add photos or other special memorabilia.

l If possible, use waterproof permanent markers and pens to write the letter because plain ink may dull over time. The paper should be acid-free so it won’t crack or deteriorate.

Indicate on the envelope when and under what conditions the letter should be opened.

Mail the letter because the postmark and stamp mark its place in history.