Do makeshift "Cloth Masks" really work in public?

Since it is now recommended by the CDC to wear some sort of face covering, alot of people are making their own due to the back order on the "surgical N95" masks. Well the question is, do they really work?

"Just because you have a mask on doesn't mean you should go out more than you were planning to and you definitely need to do the social distancing," said Dr. Chang during a FaceTime interview. "You want to be sure that it covers your nose and mouth. I see a lot of people with their cloth coverings just under the nose so that their nostrils are still exposed. It only covers the mouth and for it to have what we assume to be maximum effectiveness, you're going to want it to cover the nose and the mouth." - Dr. Michael Chang (UT Health McGovern Medical School)

See video below (