Unclog Your Drain Secret: The secret it out, how to unclog your drain and it works PERFECTLY. Pour 1 cup of baking soda down your clogged drain, and then 1/2 a cup of vinegar and cover right away!! Just let it do it’s thing for anywhere between 30 and 45 minutes and then run warm (almost hot) water for about 2 minutes. I have done this once and found out that it works greatly!!