I love preserved lemons I use them on chicken , instead of zest , on fish, make a syrup out of them I even eat them plain ( reminds me of when I was a kid and we would eat on a whole lemon all day long with lots of salt). They are so easy to make you do have to let them sit at least a couple months before you use them and they keep over a year.
Start by washing the lemons in vinegar water.
Then cut the tops and the bottoms off.
Then run a slit down the middle but not all the way.
Then down the other side also not all the way. Then open up like this.
In a half gallon (or what ever size you want) put a little salt in the bottom.
Put about a tablespoon of salt in the middle.
And fill the jar about half way.
Then push them down and add more salt and more lemons.
Once it is full of lemons push down and add more salt to cover the top.
Fill the rest of the way with fresh lemon juice, should already be about half full of juice from pushing down the lemons.
Cover and let sit a couple weeks on the counter turning upside down once on a while salt to get all mixed in. Then put in the fridge for a couple months before you can start using.
Here is what it will look like you can't tell but the juice is pretty thick. This is what I have left over from last year so I will still have some to use until the new is ready.