Here's an overview of how to apply for a Feed-In Tariff:
Choose and install your generating equipment. Options include solar panels, ground-source heat pumps, air-source heat pumps and wind turbines. Make sure the installation is done by a Microgeneration Certification Scheme (MCS) qualified professional and that you have the right certificates to be eligible for a FIT scheme. Go to Gov.uk for more information.
Get in touch with your electricity supplier and register for a Feed-In Tariff with them.
That's it! You'll get paid for the electricity you generate plus any excess you export back to the grid.