If you are not a US citizen or a permanent resident of the United States, you will have to obtain a work permit to work lawfully in America, while in the country on a non-immigrant visa. Hence, you must obtain legal authorization to work in the country and to obtain a work permit, you must file Form I-765, Application for Employment Authorization. If your immigration status permits you to work in the country as a non-immigrant and if you are eligible to work in America, USCIS will grant you an employment authorization document (EAD). Such work permits issued to non-immigrants are valid for a two year period and to continue working in America lawfully, you will have to renew this document at the end of the two year period.
As an EAD is valid only for two years, an application to renew your EAD must be filed at least 4 months ahead of the date of expiration of your existing EAD and you need to file Form I-765 to renew your expiring work permit. You must remember that there is no separate application to apply for renewal and Form I-765 that is used to apply for an employment authorization document only must be filed to renew your existing EAD. You need to file this petition at the right time as the USCIS might take around 4 months to process your petition. This form is available online and you need not visit a USCIS office to obtain this form. But you need to make sure that you are filing the current version of the form and that you are not using the outdated version.
You may choose to download this form and complete it by hand or you may file it online. Moreover, your application for renewal will be accepted only if your petition accompanies the required supporting documents and you must also submit copies of your existing EAD and Form I-94, along with Form I-765. Similarly, two passport style photographs must accompany your petition. A filing fee of $380 must be paid while submitting Form I-765 and you will have to send your application package to the address that is listed in the form instructions.
After receiving your petition, USCIS will mail you a confirmation receipt and you need to retain that receipt. You may be required to appear for an interview and appear at an application support center to update fingerprints and you need to take with you the application confirmation notice and the appointment letter that the USCIS mailed to you, to the scheduled appointment. You can check the status of your application online, by visiting the USCIS website and by entering your receipt number. You can also register for automatic updates and if you register, you will receive notifications by emails or text messages.