Sail sun shades are large pieces of fabric attached to supports in order to to provide shade. Their most common shapes are square and triangular, but they can be made in any shape. They provide a less rigid look for your yard or patio than a permanent structure while providing the same protection from sun and rain. While they're most commonly made from plain canvas or shade fabric, use colors and patterns that fit your decorating style.

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Measure the area you intend to cover and determine what shape you want it to be. The shape can be anything that suits you, but it can also be determined by what existing supports are in place to hold the shade. Keep in mind that very large sail sun shades will need a support in the middle.

Cut heavy-duty fabric like canvas or shade fabric about 6 inches shorter on each side than the size of the area to be covered by the shade. Fold the fabric under ¼ inch along one side and then fold it again to make a hem. Sew a seam along the inner edge of the folded material. Do this on all sides. Make sure all your hems are on the same side of the fabric.

Attach grommets to the corners of the sail sun shade. Grommets are round pieces of metal that snap together on each side of a piece of fabric to create a reinforced hole. If you don't have a grommet tool, place one side of each grommet on each side of the fabric and tap them together with a mallet. Cut out the fabric in the center of the hole.

Drill pilot holes where the sail sun shade will be attached. Two sides may be attached to your home or another outdoor building. Suspend other sides from existing posts or install posts by using a post hole digger to dig holes, filling them with cement and then placing posts in the cement. Let the cement cure before attaching anything to the posts.

Screw large eye bolts into the pilot holes. Put one end of a bungee cord through the grommet on the shade and the other through the eye bolt. Finish by attaching the other bungee cords to the shade and hooking them through the eye bolts.