Assemble your building materials from your local home improvement store. Take your measurements with you and they will cut the treated wood to size, saving you this step. You can find mosaic tiles there as well, but you may choose to find plates, pottery, glass and other found objects that you can break and use as a colorful, creative mosaic.
Attach one metal brace on each 4 by 4-inch treated wood post so that the metal is flush with the top of the board. Attach one of the 3 by 6-foot panels onto the braces to create the top of your patio bar.
Attach the other braces 2 feet below the top braces. Make sure the braces are level. Attach the other 3 by 6-foot panel to the braces. This is a shelf for your bar. Check to make sure both the top and the shelf are level before continuing.
Attach the 3 foot by 42-inch panels to the outside of the bar frame on either end. Attach the 6 foot by 42-inch panel to the front of the bar frame.
Break your pottery by placing the pieces in a plastic bag, covering it with a towel and hitting it with a hammer. Lay the bar on its side so that the 6 foot by 42-inch treated wood panel is facing up.
Spread thinset on a small section of the panel and press the mosaic material firmly into it. Continue tiling the board until it is covered. Let the adhesive dry. Stand the bar upright and mosaic the top the same way you tiled the front of the bar. Let the adhesive dry.
Apply grout over the tiled areas, pressing it into each space between the tiles with a grout float. Clean the tiles with warm water and a sponge before the grout dries.
Apply sealer to protect the grout from moisture and stains. If you used porous tiles such as travertine, you should use a tile sealer, rather than a grout sealer, over the entire tiled surface.