If the sound for your video is a little on the noisy side, you can clean it up using the free audio editing app Audacity. Audacity comes with a noise reduction plugin that makes it quick and easy to cut back the noise so that your audience can focus on your story or message. Here’s a very quick look at how to use the noise reduction effect in Audacity.
This is the start of a new series of tutorials I'd like to try called Quick Sound. The idea is to keep each piece short and focus on teaching a very focused element of audio recording or post processing. Does this sound interesting to you?