I have tooth sensitivity. How should I manage it?

I think I've been experiencing tooth sensitivity for some time now.

I didn't have any tooth sensitivity at all originally, so I didn't know what it was like, but now that it has started, I'm worried.

I would like to manage this before it gets worse. What methods are available?

Toothpaste that helps with tooth sensitivity or..

Are there any treatments I can receive at the dental clinic?

I suppose your usual eating habits are important too...

If you have a good idea, please share it~