Spend time away from noise. Sometimes it's simply impossible to truly get away from the noise. If you live on a busy street with lots of traffic, you know there's never really a respite from traffic sounds, sirens and honking horns. Getting away from it all is a good way to restore your emotional balance. Go to a quiet spot that's as free of sound as possible. Stay there and enjoy the silence for a few hours, until you feel renewed and ready to reenter the noise of daily life.
See if you can go for a walk in a quiet natural spot away from busy roads.
If you can't make it to a quiet outdoor space, try sitting in a library for a few hours. The librarians will make sure it stays nice and quiet.
Churches and cemeteries are also good places to find some peace and quiet.