Install and deploy the Certinia 1099-MISC Export managed package. See the Salesforce help topic Install a Package.
[Optional] If the legal name that you want to appear on Form 1099-MISC differs from your Salesforce Account name, then add the Account Legal Name field to your Account detail page layout. See the Salesforce help topic Customizing Page Layouts.
Set up your 1099-reportable Accounts (suppliers and contractors):
In the Sales & Use Tax Information section, select Federally Reportable 1099.
In the same section, select a default category of 1099 income tax, such as "1 Rents".