Boil water and pour it slowly down the drain
Add baking soda to the drain
Pour vinegar into the drain
Wait 15 to 30 minutes
Flush with hot water
Remove and clean the sink stopper or strainer
Place a bucket under the P-trap
Unscrew the P-trap and clean out debris
Reassemble the P-trap tightly
Use a plunger over the drain
Seal the overflow opening if present
Use a drain snake or auger
Insert the snake into the drain and rotate it
Pull out any clog material
Run hot water to test the drain
Clean the garbage disposal if the sink has one
Reset the garbage disposal if needed
Check the dishwasher hose connection for blockage
Avoid using chemical drain cleaners if possible
Call a plumber if the clog remains