Apply wax to one section of your car and then buff it before moving on.

On TV and in the movies, the average kid at the beach is able to build incredible, multi-story sand castles that bring to mind the storybook palaces of kings and queens. So why is it that when you sit in the sand with your own child, you only seem able to construct a big, crumbling lump with a moat surrounding it? Well, you don't have to have a degree in architecture to build a truly impressive sand castle, but you do need to know a few simple secrets.

Ray Karch is a lawyer, magician and sand castle creator. The winner of the 1999 US Open Sand Castle competition, he also owns Castles by Karch, where he gives group and private lessons in sand castle construction and builds custom castles for special events. Here he tells us the secrets to building the sorts of sand castles seen in TV shows and films:

• Powdery sand. According to Karch, the best sand for building castles is fine and powdery. The coarser the sand is, the less useful it will be. The sand found in the average children's sandbox is far from ideal.

• The ball test. When you find a likely spot on the beach, walk down to the waterline where the surf has retreated to leave wet sand. Pick up a handful, press it into a ball, and toss the ball back and forth between your hands. If it stays together without cracking, you've got the right sand for building a castle.

• Mold. To create a truly professional-looking castle, you'll need to use a sandcastle mold. Karch recommends packing the sand firmly into the mold as you fill it. Fill the mold a quarter full, pack the sand, and then fill it up half way and pack again. Continue until the mold is full, and then maneuver it into place, tap the sides and lift.

• Board. Another trick that the pros know is using a board to make straight edges. Stairs are easy, according to Karch. You just push the board down, pull back, and then repeat this action to make as many steps as you want.

• Keep it damp. If the sand dries out, the structure can weaken and crumble. Bring along a bucket of fresh water and a spray bottle, and make sure to keep your creation damp.

For more information on sand castles, check out the following organizations and websites:

Sand Castle Central
www.sandcastlecentral.com

The Internet Center for Sand
www.netaxs.com/%7esparky/sand.html

Sandscapes
www.sandscapes.com

Sandworld
www.sandworld.com

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