Pour directly down the drain. If it clumps at the opening, use a dry spoon or your fingers to push it down. Try to get as much of the powder into the drain as possible, rather than leaving it in the sink basin.
Boil 2 cups of water and pour it slowly down the drain. This softens soap scum and grease.
Here is the proper way to use this chemical reaction to clear your shower drain, why it works, and when to call it quits. how to unclog shower drain with vinegar and baking soda
Cover the drain with a cloth or drain cover to keep the reaction inside the pipe. Wait 15–30 minutes . For tough clogs, wait up to an hour.
The reaction is known for its fizzing and bubbling. While this looks satisfying, the "magic" isn't just in the bubbles. The rapid expansion of the carbon dioxide gas creates pressure that helps dislodge gunk stuck to the pipes. Furthermore, vinegar is a mild acid that helps dissolve mineral deposits, while baking soda acts as a mild abrasive that can scrub the pipe walls as it moves through. Pour directly down the drain
Pour 1/2 to 1 cup of dry baking soda into the drain. Try to get as much as possible down into the pipe rather than just sitting on the grate.
While effective for maintenance, this natural solution has its limits: Boil 2 cups of water and pour it slowly down the drain
As soon as you pour the vinegar, immediately cover the drain with the drain cover or a wet rag. You want the fizzing reaction to occur inside the pipe, pushing down against the clog, not bubbling up harmlessly into the shower pan. Covering the drain forces the pressure downward.
Finish by pouring another pot of boiling water down the drain to wash away the loosened debris. When to Use This Method (And When to Call a Pro)
If you cover the drain after pouring the mixture, the trapped gas creates pressure that helps push the blockage through the pipes.
Boil a kettle or pot of water and pour it directly down the drain. This helps melt soap scum and soften grease to prepare the clog for the reaction.