She Failed Penmanship As a Child. Now She’s a Successful Calligrapher.

As a young girl, Ellen Weldon probably never dreamed she would grow up to become a calligrapher.

“The first and only F I ever got was in the sixth grade for handwriting,” said Ms. Weldon, 67, who has since perfected her penmanship and has been running Ellen Weldon Design, which has been offering calligraphic services and invitation design services for everything from weddings to business correspondences to fashion events, for nearly four decades.

Her services aren’t cheap: Couples who hire her for their weddings can expect to pay from $40 to more than $100 per invitation, which “is supposed to arouse curiosity and excitement for the event,” Ms. Weldon said. “My goal is for people to save them. It’s like a gift in a way.”

For Ms. Weldon, who works in Manhattan, the wedding business has been a family affair. Her mother was Sylvia Weinstock, the wedding cake visionary known by fans as the “queen of cake” for her ornate, colorful and realistic confectionery designs. Ms. Weinstock died last year at the age of 91.

Sometimes Ms. Weldon and her mother would work on the same wedding without even knowing it: “I was involved at the beginning,” Ms. Weldon said. “My mother was at the end.”

So many of us are hesitant to hand-write things now because we’re fearful we’ll mess up and have to start over. What do you do when you make a mistake?

The stakes are high; we deal in perfection. Our work is like preparing for a Broadway show that goes on for only one night. I’m an absolute stickler for correct spelling, which we triple check. Nothing is worse than receiving an invitation with your name misspelled.

Some can be fixed with techniques that I have developed over the years. Most involve an X-acto knife, but I can’t give away my secrets. If it cannot be fixed, you have got to start over. You can never cross out.

Have you had any crazy mishaps?

About 15 years ago, I was hired to do the wedding invitations, welcome notes, dinner menus, seating cards and the wedding program for a couple who were getting married in Paris. The wedding program was written in English and French.

A day or two before the wedding I was told one page had the English and French reversed and needed to be replaced. I hopped on a plane, landed, and spent the next eight hours untying 350 ribbons, taking out the incorrect page, inserting the new one, and retying all the ribbons the day before the wedding. The bride and groom never knew there was a problem.

How do you keep your hand steady? That’s another element of your profession that seems quite stressful to the layperson.

I’ve become steady over the years. It was a matter of training, and holding the pen while breathing steadily. I don’t hold the pen too tight, so it’s flexible and loose. You want a rounded, soft pen you can manipulate.

How did you end up excelling at something you originally failed?

After I got the F in penmanship, I got a book on calligraphy. It had practice pages, and really helped you understand how to do calligraphy by teaching the basics. In high school my aunt was studying calligraphy and she took me to her class. That was an eye-opener. I went to Smith College as an art major and took a class in calligraphy there.

How did your career start?

My first job post-college was designing Christmas cards and addressing envelopes for Cartier. They really exposed me to proper fonts and designs, etiquette wording and how to succinctly phrase an invitation. I was 23. Estée Lauder came in one day and saw what I was doing and told me to be at her office at 2 that afternoon. My manager told me to go, so I did.

I started doing her private dinner parties. Then it was working for Estée Lauder brands: Clinique, Aramis and Prescriptives, among others, handwriting their invitations and envelopes to a variety of events and dinner parties.

When Cartier rejected a Christmas card I created, I went to Saks Fifth Avenue to see if they wanted it. They did. They wanted 10,000. Cartier told me I could only be exclusive to them. I knew the engravers and the printers Cartier used, so in 1982, after working there for six years, I left to start my own business.

What kind of special instruments do you use?

I use 12 different pens, each which offers a different thickness, flexibility and style of the letters — whether it’s bold, delicate, slanted, upright, written tiny or large, modern or curvy. And I know 50 different fonts.

Some scripts or styles like Spenserian, which comes from the 19th century England, are extremely swirly and the letters are very connected. Those take a great deal of patience and an extremely steady hand. I don’t drink coffee those mornings.

What advice can you offer couples meeting with stationers?

Know your invitation budget; the number of invitations you’ll need; what mood you’re trying to set; and what kind of wedding you’re having, meaning is it a luncheon or formal black-tie dinner; and your color scheme. It helps to show us a Pinterest board or Instagram things you like. If you have a wedding planner, bring them. And always ask about a timeline.

What can you offer the couple on a budget who still want calligraphy?

I have exclusive fonts I’ve created that could be used for the lettering on your invitations, which is less expensive than me hand lettering with the original artwork. Go with lighter card stock. Don’t have reply envelopes, have people email their responses instead. Make sure your invitation size are within U.S. postal regulations so you’re only using one, first class stamp instead of getting charged more because it’s oversized. We’ve also had people pick up their invitations and stuff, stamp and mail them themselves.

What are some of the most innovative invitations you’ve created?

We did a pyramid shape that was covered in silk. When you opened the pyramid it played music. We did a box that revealed a disco floor that had pulsing multicolored lights when you opened it. The message inside was written on the plexiglass that was on top of the lights. And we did a custom musical snow globe.

Does all the handwriting and other custom work take a toll on your hands?

Ten-plus years ago it became very painful to hold the pen. The tendon that was holding my thumb became inflamed so I had surgery. I was out of commission for six weeks. Now my hand is 100 percent perfect.

This interview has been lightly edited for clarity.