Summarize this article in one sentence.
Cut the lemon in half, from tip to tip. This makes a more flexible lemon peel, easier to squeeze. If you have a hinge-style hand juicer cut them crosswise instead for a better fit. The mesh will catch the lemon seeds and pulp, letting the juice drain through. An all-purpose juicer will put a great deal of bitter pith in your juice, and its metal blades may corrode over time. Buy a specialized citrus juicer for better results.  If using an all-purpose juicer, peel the lemon first or wash it thoroughly to remove trace pesticides. Many experts agree that hand-squeezed juice tastes better, possibly because an electric machine scrapes away too much pith, or fails to break out flavorful oils from the peel.

Summary:
Cut the lemon lengthwise. Place a mesh strainer over a bowl. Buy an electric citrus juicer for large quantities.