Here is the jupyter notebook used as a demo: astropy.io.fits_demo.ipynb
To open the jupyter notebook, save it somewhere on your computer. Open a terminal window, navigate to that directory and type 'jupyter notebook'. Then, select the astropy.io.fits demo.ipynb file under the browser tab.
Here is a .fits file that you can use to practice on test.fits but you can use any .fits file. Save it in the same directory as the jupyter notebook.
You'll need jupyter, numpy, astropy and matplotlib