The biceps muscle is located at the front of your upper arm. To build this muscle most efficiently, focus on preacher curls. The website Home-Gym-Bodybuilding.com explains that the preacher curl movement is by far the strictest, most productive exercise to develop large biceps. You must use a specially-made bench to perform a preacher curl. The position of your arm and the support under it allow you to lift the heaviest possible weight. You can easily build such a bench at home.
Find a sturdy kitchen chair and position it in front of a wall. The chair should be positioned 2 feet away from the wall and turned sideways. In other words, if you sit on the chair now, either your left or your right shoulder would be next to the wall, depending on which way you turned the chair. Either side works, but for clarity, turn it so the right side of the chair faces the wall.
Place the 3-foot-long piece of wood against the wall as if it were an additional layer of wallpaper. The wood piece should be facing the chair's right side. The short side of the wood piece should be down and touch the floor. Now lean the top end of the wood piece away from the wall until it rests on the right side of the chair's seat. The low end of the piece remains in the original position, which is where the wall meets the floor. Make sure the top end of the wood piece reaches about 1 inch over the chair edge to avoid it from sliding off. To ensure you have done this correctly, get behind the chair on your knees and look at the leaning wood piece from the side. The piece should be in a 45-degree angle away from the wall.
Fold two of your bath towels so they become as narrow as the chair seat. Do not fold them both ways so they become a square but stay as oblong as they were originally. Place them, one on top of the other, so they cover the chair seat and the upper half of the wood piece. If they do not cover both seat and piece, find bigger towels. The towels serve as cushioning, making it more comfortable for you when you perform the curl. Fold the third towel into a square and put it on the left side of the chair where you will place your knees when you perform the preacher curl.
Grab a dumbbell and position yourself on the left side of the chair, your knees on the folded towel. You should be facing the wall and the chair back should be to your right. Lie your body over the chair and place the arm with the dumbbell on the wood piece. Make sure you position yourself close to the chair to hold every part of your bicep curl bench in place. Place your armpit over the top part of the wood piece, which is where the wood piece and the chair edge meet. Extend your arm and begin curling.