Hi Lmendiaz: There are a lot of ways, here are a couple: Pour baking soda and vinegar down the drain and let it sit for a little while, maybe 1/2 hour, and then pour HOT water down the drain.
I've used the baking soda and vinegar trick with great results. I've also used a really long zip tie if you think hair is the problem. What I do is make fairly close together cuts along one edge, nearly to the other side, twist it around until it stays twisted - or not, some ties are just stubborn! - shove it down the drain until you feel the blockage and twist again several times and pull out slowly. If there is hair down there, the zip tie will pull it out. You may have to do it a couple of times, then I'd do the vinegar baking soda thing to be sure. If nothing helps, you can remove the U trap - it only screws/unscrews from one end - and take any clogs out from there. Be sure to put a pot under the trap because gunk will come out, and it's not pretty Then, clean out the trap and the pipes hanging down and replace everything. Plug the sink, fill it with water and then let it run out to be sure there aren't any leaks. You may want to use some Teflon tape when you put the U trap back. Good luck
Cover the overflow hole with wet paper towels. Pour some baking soda down the drain, then pour some vinegar down. Immediately cover the drain with a cloth and press down. The pressure from the foaming action should push the blockage through. Otherwise you may need a plunger or rodding if the clog is further down the line.
My favorite way is to pour some baking soda down the drain, followed by some plain white vinegar. I let it fizz and soak for 15-30 mins the flush with warm water. I do this regularly with my drains and it helps keep them clear. There is no need for harsh chemicals. Just be sure to rinse the vinegar well. Wishing you the best!
Walmart has Draino with a really useful plastic snake attached to go down the drain first inexpensive like $7. You'll be amazed the guck & hair it can remove - then use the Draino. Then follow up regularly with the vinegar/baking soda rinses to keep it unclogged. You can keep the snake & use it regularly to stop the problem. Worked great for me - Good Luck
Baking soda vinegar let sit a hour then wash down with very hot water
DO NOT USE DRAINO!!. I've seen it come out of a pipe in a solid piece. Buy or rent a small drain snake. Best is to remove the trap and insert the snake into the pipe going out of house. Put in slowly until you feel a little resistance. Twist clockwise several times then pull back. Clean the snake and re-insert until you feel no more resistance and comes back clear. After this use the vinegar/baking soda on a regular basis and be careful about washing hair or combing it in bathroom. It piles up slowly. The long zip tie or maybe a pipe cleaner would work well too.
For under $2 you can buy a plastic tool made for removing hair/gunk from bathroom drains without having to remove the stopper. Once you've got the drain cleaned, fill the basin as high as possible with HOT water and allow the water pressure to flush out the rest. I pour boiling water down our drains about once a month.