Keep trash out of the sink drain. Perhaps the most important part of keeping your drain clean is being mindful of what you put in it. This is especially true for bathroom sink drains, which will inevitably accumulate natural detritus, such as hair. As a rule of thumb, if you’re unsure whether it’s okay to go down the drain, throw it away instead.
Avoid washing dishes or disposing of any food products in the bathroom sink. Don’t dispose of personal care products, such as cotton balls, dental floss, or bits of toilet paper in the sink drain. Take care not to let the small round liner underneath the lid of personal care products go down the drain.
Use less soap and other products. Even soap and other things that you regularly dispose of in your bathroom sink, such as toothpaste and shaving cream, can contribute to build up in your drain. As such, get in the habit of using smaller amounts of these products.
A small dollop of toothpaste is plenty, and a single pump of hand soap is sufficient to wash your hands. Let the water run down the drain for a few seconds after using soap or toothpaste so it gets flushed away.
Avoid commercial drain cleaners. There are a lot of reasons not to use commercial drain cleaners that rely on chemicals. They can corrode your pipes and damage other components of your fixtures and plumbing system. They are also toxic, and can work their way into the ground water in your area.