Ensure that you have legal standing to contest the will. You must demonstrate that you will be wronged by the will and its terms. Spouses and relatives of the testator -- the will’s author -- as well as named beneficiaries, creditors and public agencies all may have legal standing to contest the terms of a will.
File a petition to strike down the will within three months of the time it is filed in probate court. State law provides for exceptions in certain cases, but if you fail to meet the deadline, you must show good cause to the court as to why you did so.
Prove that the will is legally invalid in your petition. The will may not have been signed, notarized or witnessed. The testator may have been incapacitated, unduly influenced by a beneficiary or unaware of the extent of the estate at the time of writing the will. The will may also show that the testator was unaware of all heirs, or may show an irrational division of the estate. You may also show that the testator revoked the will by physically destroying it or creating a new will that has not been subject to probate.
Attend a court hearing, at which you and/or your attorney will argue that the will is invalid according to one or more legally valid grounds. The hearing will be attended by yourself as well as any other beneficiaries who wish to take part in the proceeding and testify as to the validity of the will. The judge will consider the arguments and render a decision, which may allow the will to be carried out by the assigned trustee, or strike down the will and order a new distribution of the estate.