Where do I put this coding?

So… I followed a tutorial, and in the end image sliced my websites background image with PhotoShop so that my menu bar can be click-able in certain hard to do spots… I have a folder with lots of images now.. and I have an html coding… Where do I need to put this coding to get this to work?

EDIT 1: I used this tutorial: https://www.createblog.com/photoshop-tutorials/736-photoshop-image-maps/

I am also using a twenty ten child theme.