Cut the lemons in halves or quarters. Squeeze enough juice out of some of the lemons and add kosher or sea salt to the lemon juice. Add the salty lemon juice to the jar, followed by some lemon pieces, more juice, lemons. Make sure that you have enough lemon/salt juice to cover the lemons in the jar...I like to add fresh bay leaves, peppercorns and garlic cloves to my jar. Let rest on counter for a few days. After that, place in fridge. Every couple of days, turn jar upside down. They will be ready in in a few weeks. They will last in your fridge up to six months. You can use preserved lemons on so many dishes that call for lemon. The Mid-East uses preserved lemons alot.