The lawyer for the H-1B employer will surely inform you of the documents that are necessary. But in general you need all evidence showing that you are currently maintaining lawful L-2 status (including your spouse maintaining L-1 status), and your educational documentation showing that you have the equivalent of a U.S. bachleor's degree in a field that is required for the H-1B job. If your degree is not from a U.S. university, you will need an equivalency evaluation.
Documents showing that you meet the academic (or equivalent) qualifications for the offered specialty occupation, and that you and your spouse (marriage certificate is required) are maintaining respective nonimmigrant status if the H1B petition is being filed as change of status rather than consular processing. Your current immigration attorney will guide you.
The information contained in this answer is provided for informational purposes only, and should not be construed as legal advice on any subject matter, nor should it be viewed as establishing an attorney client relationship of any kind.
You (the employee) cannot file the petition. It must be filed by the employer. There are a host of documents needed to successfully apply for H-1B, and timing is absolutely critical. Your employer should absolutely work with an immigration attorney. If they've ever done H-1B petitions before, they'll have an attorney they can contact for this. I'd suggest you speak withe HR department first, to see if they know an attorney. If not, then find an immigration attorney in your area. Cheryl
Please note that by answering this basic question I have not entered into an attorney/client relationship with you, your prospective or actual employer, or any other party. I urge you to consult personally with qualified immigration counsel before making any decisions about your future plans related to immigrating to the U.S.