Take measurements of your kitchen. Write down the number of empty feet between the cabinets and any nearby walls or walkways.
Sketch a drawing of the bar you want to install. Write down the width and height of the bar. Ensure that you leave at least three feet of space between the bar area and any cabinets or appliances. This space is necessary for adequate walking space and the opening and closing of appliances.
Cut out a large piece of cardboard that is equal to the measurements you sketched. Lay the cardboard cutout in the area of the kitchen where you want to install the bar. Walk around the cutout to ensure it is comfortable and provides enough space. This will give you a feel of the bar. Adjust the location of the cutout as necessary.
Place painter's tape around the perimeter of the cardboard cutout. This marks the location for your cabinets that will hold the bar top.
Shop for cabinets. The cabinets will hold the counter for the bar area. You can find good deals by buying secondhand. You can try to find bar-height counters for a more authentic feel. You can also construct a platform with 2-by-4 inch boards and a nail gun so you can prop the cabinets on top of it to provide for extra height.
Place the cabinets inside the areas you marked with the tape. Clamp the cabinets together with a C-clamp.
Attach the cabinets to each other. Drill three pilot holes with a drill bit and drill into each faceplate of the cabinets. The screws should be placed so they do not interfere with the opening and closing of the doors and drawers. Drill three 2 1/2-inch wood screws into the pilot holes.
Attach the cabinets' backs. If your bar is on a wall, screw 2 1/2-inch wood screws into the back of the cabinets through the wall. If your bar is freestanding, place a wooden spacer in between each of the cabinets. Screw the 2 1/2-inch screws through each spacer so the cabinets are firmly attached to each other.
Add decorative paneling to the back of the bar if it will be visible. Use a table saw to cut out the paneling of your choice. Use a nail gun and add nails about every 6 inches.
Install your countertop. You might need a subcounter of plywood if you install a heavy countertop, such as granite or marble. Cut the plywood to size and screw in place with 2-inch long deck screws. Use the appropriate type of countertop adhesive for the type of countertop you are installing.
Add finishing touches. Install base molding to the bottom of the bar by cutting the molding to size and nailing in place with a nail gun. Install bar related accessories, such as a bar light, bar stools, bar pole or draft system to give it a more authentic look.