If you wish to work in the United States for a temporary period you will require a nonimmigrant work visa. You cannot work on a visitor or business visa, or under the Visa Waiver Program (VWP).
Unlike some countries, the United States government does not issue work visas for casual employment. In general, work visas are based on a specific offer of employment. In most cases, a petition must be filed and approved by the United States Citizenship and Immigration Services (USCIS) before applying for the visa at a U.S. Embassy or Consulate. For more information on temporary worker visa types, click here.
More information about the petition process, eligibility requirements by visa category, and numerical limits, if applicable, is at the USCIS website. Once the petition is approved, USCIS will send your prospective employer a Notice of Action, Form I-797. You will need to provide the receipt number that is printed on your approved Petition for a Nonimmigrant Worker, Form I-129, or Notice of Action, Form I-797, to schedule an interview.