You don’t need to surf to be a professional beach bum; if you get good enough, you can travel the world carving sandcastles with a palette knife and an ice cream scoop. That’s what Lucinda “Sandy Feet” Wierenga does. Ms. Wierenga was this year’s winner of the Travel Channel’s Sand Blasters competition. She’s in Italy now, giving castle-building demonstrations. And Ms Wierenga will be here from 2 to 5 p.m. on Tuesday, August 5, to show off her skills as part of the Fourth Annual Sand Sculpture Contest, hosted by the Edgartown Board of Trade.

How do you build a professional sand castle? When phoned for an interview last month, Ms. Wierenga was heading to the airports, trying to catch a flight to Europe before Hurricane Dolly hit South Padre Island, Texas, where she lives. She had time to give a single piece of advice: “Water. The biggest mistake is not enough water. It takes a lot of water.”

Then she added a piece of good news and bad news: The sand on Martha’s Vineyard is too coarse to allow for world-class beach construction projects. That fact limits the techniques builders can use — and levels the playing field.

Janice Donaroma, vice president of the board of trade and the organizer of the event, agrees. She says that when she learned that the sand here is unsuitable for professional sand sculpting, she refocused the competition, and the change was for the better. “I knew I had to keep it homespun which allows everybody to participate.” She added: “People work their vacations around the contest because it is such a great family event.”

The competition — held on South Beach (the right fork) on August 6, the day after the professional demonstration — has two categories, adult and junior. The rules are simple: Building tools may be used to shape the sculpture, but they cannot become part of it. Groups of builders must be eight people or fewer. And by the end of the day, participants need to clear out all non-biodegradable items they have used. One new rule has it that adults cannot help children in the junior category, although children can still pitch in for the adult competition. The contest goes beyond castles to sculptures. Winners in the past have been a Viking, Mount Rushmore, and, yes, a very large sand castle.

The contest also features a People’s Choice Award, in case the public disagrees with the jury.

The Tuesday workshops and demonstrations will be held in a specially built sandbox in the mini-park on Main street in Edgartown. A preview of Ms.Wierenga’s methods can be obtained by accessing her Web sites, at sandyfeet.com and sandcastlecentral.com or by paging through her 2005 book, Sandcastles Made Simple.

There she explains the importance of good sand and using a lot of water. In the book, Ms. Wierenga describes the “Interstitial Bridges” between grains of sand that help hold a castle together. She goes on to talk about the importance of letting the water drain, compacting the slurry to form structures, and of course carving the resulting mound into something pretty.

Ms. Wierenga explores three methods for building a sand castle. Soft-packing involves “shoveling up a big mound of sand, pushing it into a rough approximation of the desired shape, throwing water on the surface to keep it in place, and then using brute force to pack the sand before carving the detail.” This approach requires no equipment, but it calls for a lot of physical work. “The only way to attain altitude is to shovel up a bigger base pile.”

Hand-stacking is a “‘patty-cake’ method.” You take wet sand in you hands and squeeze it into pancakes or bricks that you pile one on top of one another. “You build with handfuls of premixed super-wet sand scooped from a hole or a bucket and create structures that are already very close to the mass they will have after they are carved.” This approach allows for taller structures but requires more skill: “The concept is simple, but it takes some practice to master.”

The third method involves working with forms, like the plastic molds that children use on the beach — but on a much larger scale. Ms. Wierenga recommends bottomless buckets made of large plastic sheets that are rolled and secured with clamps. You pour in sand and water, tamp down well (with your feet, if necessary) “until there is no more give,” and then open the clamps and peel back the plastic. If you’ve got the right sand — and of course, here, you won’t — you’ll get really tall towers. The disadvantage of the form method is that you need to bring equipment to the beach.

The ice cream scoop may help you gouge a rounded indentation in a tower top, and the palette knife will serve for incising decorative flourishes.

After a few days at the beach, will you be ready for your world tour? Probably not.

But then Ms. Wierenga never imagined her life taking the turn it did. She started out as high school English teacher.