There is no mechanism in the United States to incorporate on the federal level; rather you register it in one of the 50 states. A company interested in incorporating (or forming a partnership or limited liability entity) must contact each state’s licensing authority individually. The paperwork to set up your corporation or LLC is relatively straightforward; you can either find an attorney to work with you or register online through an online legal filing service. A company set up through a more affordable online service is just as legitimate as one set up through a lawyer, but a lawyer will be able to answer questions pertaining specifically to your business.
You’ll need to decide on a business type. For foreign companies/individuals, there are two main business entities: the C Corporation and the LLC (Limited Liability Company). The LLC is usually treated as a “pass-through” entity for taxes, meaning any profits pass through to the owners (reported on the individual level). A C Corporation pays taxes on any profits (reported on the business level). You can talk with an accountant/tax attorney to determine the best entity.
When it comes to deciding which state to register in, there are a few things to keep in mind. If you will have any kind of an office or physical presence in the U.S., then you should incorporate in that state. If you will not have a physical presence in the U.S., then you can incorporate in any state. Delaware, Nevada, and Wyoming are traditionally considered the most business-friendly states for incorporating.