Put water in a pot, put the glass bottle upside down, boil it, and disinfect it with steam. (You have to sterilize it with hot water to prevent mold.)
Sprinkle the lemon with baking soda and scrub the skin with a brush for the first wash.
When the water boils in a pot, roll the lemon for 20 seconds, wash it for a second time and rinse with cold water.
Rub the skin with a thick salt, rinse it with cold water, and use a kitchen towel to remove moisture.

Cut both ends of the lemon into thick slices and slice about 0.3cm.
Remove all seeds from the sliced lemon (the white part of the seeds and skin causes the bitter taste of lemon syrup).^^)

Mix sliced lemon, sugar, and honey in a wide bowl and place them in a sterilized glass bottle when the sugar melts a little.
(The ratio of sliced lemon to sugar + honey is 1:1. If you skip honey, you can set the ratio of lemon and sugar to 1:1.)
Let the sugar ripen at room temperature for about 2 days until it is completely dissolved and refrigerate.