I am often asked what makes a valid will.
First, there must be a writing. This can either be in your own handwriting (a holographic will) or on a word processor (signed and notarized).
Second, you must know what you are doing (having capacity).
Third, you must know what your assets are.
Fourth, you must know who your leaving your assets to.
Finally, you must not be under the influence of another (i.e. you are doing it on your own free will).