From the wonderful folks at Aish.com!

SELECTING A SITE

To build your own Sukkah, first select a site that has nothing hanging above it -- i.e. a roof or a tree. The Sukkah floor space must be at least 27 inches by 27 inches 967 cm) -- the minimum space for most of a person to sit with a small table. If you don't have a yard, then an apartment balcony will do just fine -- provided it has no roof.


THE WALLS

A "kosher" Sukkah needs at least two complete walls and a small part of a third wall. The walls can be of any material, as long as they are sturdy enough to withstand a normal wind. The walls should be at least 38 inches high (96 cm), but not higher than 30 feet (9.6 m).

You don't have to build walls especially for the Sukkah; you can use the side of a building, or even a hedge of bushes. And if you can find an area that is already enclosed by 2 or 3 walls, then your job will be that much easier!


THE ROOF

The Talmudic term for roof material is S'chach, from the same root as the word Sukkah. The roof must be made from material that grows from the ground -- i.e. branches or leaves (but not metal, or any food). If you're using unfinished boards, they cannot be wider than 15 inches.

Also, the material must be presently detached from the ground -- i.e. don't just bend a tree over the top of your Sukkah!

The roof material can only be added after the requisite number of walls are in place.

The roof must be sufficiently covered so that it gives more shade than sun during the daytime. Yet it should be sufficiently open so that the stars are visible through the roof at night.

Since the Sukkah is designated as your "home" for the next seven days, it is customary to decorate it nicely. Many people hang fruits and flowers from the ceiling, and tape posters of Jerusalem and other Jewish themes on the walls.

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We made ours yesterday...it took almost the whole day since we had to totally redesign it so we could fit more people...now it's the same size as some of the shul sukkah's around here.

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