By air: Augusta Regional Airport (AGS) is a small regional airport served by American, Delta, and United with connections to their respective hubs (Charlotte, Atlanta, and Washington Dulles). Fares are often higher than you'd expect for the distance, and travellers with flexibility sometimes fly into Atlanta instead and drive.
By car from Atlanta: The most common approach is the two-hour drive east on Interstate 20. The road is fast and straightforward. Rental cars are available at AGS and at Atlanta's Hartsfield-Jackson Airport.
By train: Amtrak's Silver Meteor and Silver Star stop at Aiken, South Carolina, about 18 miles west of Augusta. Aiken is a small town with limited onward transport, so you'd need to arrange a taxi or rideshare from the station into Augusta. It's workable but not seamless. The trains run between New York and Miami via this corridor.
By bus: Greyhound serves Augusta with connections to Atlanta, Charlotte, and other regional cities. The bus station is downtown.