If you don't already own one, click here to find out more about the Robert Bentley Volkswagen Fox Repair Manual. The "Bentley Manual" is specifically written for the Fox [there are others for most VWs and other makes made as well], and contains almost all you need to know to keep your Fox in excellent condition.
Furthermore, I am only posting information that I have either verified myself by having performed the work on my own cars, or that I have received from fellow Fox owners and believe is completely true. Not everything is advised to be undertaken by beginners, but as you get more comfortable with your car you will find that most of the work is straightforward and doesn't require expensive tools or complex work. The standard disclaimers apply: all information posted here and on my web site in general is here for informative purposes. While I have taken great care to ensure the accuracy of all the information, if something doesn't seem quite right in my instructions, please use common sense.
Lastly, I would like to encourage everyone to work on their cars by themselves. I have the luxury of having a father who is a car mechanic and who owns and runs his own shop. With his guidance, instructions (and very often his help), I am able to do almost anything with my car. But the majority of basic upgrades can be done by anyone who can use a screwdriver, other tools, and who has common sense :) It may seem overwhelming at first, but believe me, Volkswagens (especially older ones like our Foxes) are built in a very simple and straight-forward manner, and are extremely easy to work on. The Bentley manual, combined with some online help from fellow Fox owners (here and here), will help you fix or upgrade almost anything!
Once you've read through the above, you can read up on specific upgrades that are outlined below. I've attempted to divide up the information into logical sections: