A Will must be signed by the person whose Will it is, dated and the signature witnessed by two independent witnesses. This means that the witnesses cannot be relatives of the person writing the Will and they cannot be named as beneficiaries in the Will. They also cannot be married to anyone who is a beneficiary.
A Will must be written although it can be printed or handwritten. It must not be marked in any way or damaged. This means that there should be no crossings out or holes made by staples or paper clips. If you are at all uncertain whether the Will is valid or not, please consult a probate professional.