Train: If you're feeling adventurous and want to make new friends, take MARTA (it's smarta.) The easiest and most budget-friendly way to get from the airport to Midtown is by hopping on MARTA. The ride is around 30 minutes; just catch any train heading north from the airport and hop off at the Midtown station.
Car: If you're looking for a convenient option, you can take an Uber or a cab! Taxis offer fixed rates, which can be really handy. Plus, the airport is just a quick 20-minute drive to and from Midtown.