Check for spelling of names, dates and make sure that the terms and conditions reflect your intent.
You must understand its contents. If you are signing a will that was prepared for you, you should not make extraneous marks on the document. Do no cross out provisions you do not want. In some jurisdictions crossing out portions of the will may invalidate the entire document. Further, such markings will inevitably require more administration and cost in the settling of your estate. It will likely cause your executor (or personal representative) to go before a judge for a ruling on the markings.
If you find the will acceptable, you may proceed with executing (signing) the documents in accordance with the following instructions.
Select a notary public
Most jurisdictions do not require that a notary public notarize your signature on your will. However, the purpose behind having a notary's jurat is to avoid future litigation. Also, if your state provides what is commonly referred to as a "self proving affidavit" attached to your will, then the notary's signature will be required. The "self proving affidavit" is essentially the sworn testimony of the witnesses that they believe you were competent to sign the will, and they saw you sign it. In some states, without this the self proving affidavit, the witness will have to testify after your death that they signed your will.
The notary you select should not be related to you by blood or marriage, and should not be a party named in your document (specifically or by class).
Select two witnesses.
You should select two (2) witnesses to witness your execution of the will. Your witnesses should both be over 18 years old (21 in some jurisdictions), neither of them may be related to you by blood or marriage, neither of them may be a beneficiary or fiduciary named in your will. They must both be completely independent parties of you.
Although not a requirement everywhere, to be safe, you should ask both witnesses to serve as your witnesses in the presence of each other and the notary.
Although not required in every jurisdiction, it is a requirement in some jurisdictions that you, the witnesses and the notary all are present in the same room during the entire signing process. To be safe, you should follow this formality strictly.
Formalities for signing your will.
The witnesses are testifying to the fact that you have testamentary capacity. Testamentary capacity, although defined differently in every jurisdiction, generally means that you have the requisite mental capability to know (1) the nature and extent of your property, (2) the persons who are the natural objects of your bounty (your children), (3) the nature of the document you are signing and the dispositive provisions, and (4) how these elements relate so as to form an orderly plan for the disposition of your property. Some States also require that you acknowledge that you have reviewed the document.
Answer these questions for the witnesses: who are your children, what are your assets, that you have reviewed and understand the term of your will and that you are signing your last will and testament as a part of your overall estate plan. Your witnesses should acknowledge that they believe you possess testamentary capacity.
Signing your will.
Although not a requirement in every jurisdiction, it is a good idea to sign at the end of the text of each page of your will, particularly where the text does not fill the entire page. For jurisdictions that are a part of the international wills treaty, signatures at the bottom of each page are necessary - especially if you have or may acquire international property.
You should then sign your will in two more places: the attestation clause and (if applicable) on the self proving affidavit.
Your witnesses should then sign at the end of the text on each page near your signature. Your witnesses should then sign at the attestation clause and (if applicable) on the self proving affidavit.
The notary should then sign the jurat or acknowledgment (if applicable) being sure to properly fill in all jurisdiction information and dates.
You should make certain that any blanks for the date of execution are properly filled in during the signing of your will.
Additional resources provided by the author
The best place to find additional information regarding signing your Will is from an attorney qualified to practice in the state of your residence. If you cannot afford an attorney, you may be able to locate dependable resources with your State's Bar Association, a law school in your State, or a legal aid clinic. If you are in the military, your JAG office will help you with both drafting and signing your will.