One of the first steps you can take to ensure that your will is protected, is to keep the original copy of your will in a secure location. At home, consider using a fireproof box or a safe. You also might invest in a safety deposit box at your local bank.
Additionally, you should also make a copy of your will. While most jurisdictions require the original, a copy can be used if the original has been lost or stolen. Please be advised though, additional proof as to the authenticity of a copy might be required.
Lastly, although you don't have to provide details of what's in your will, it is recommended that you inform your loved ones that you have, in fact, created a will. Advise them that the will does exist, and also the location of the will, should they need to access it.