First task upon arrival! Local SIMs or eSIMs are cheaper and faster than roaming. You can buy them at convenience stores or roaming centers in the arrivals hall.

You'll need some cash (Won) to get to the city. Airport exchange booths are convenient but rates can be pricey. It's best to exchange just enough for transport.

With heavy luggage, the 'Limousine Bus' is way easier than the subway. You must buy a ticket at the counter or kiosk BEFORE going outside.

Tell the destination and number of people. Major spots like [Gangnam], [Hongdae], or [Dongdaemun] are covered. You can pay by credit card.

Limousine buses stop at major hotels. Check with the driver before boarding. Telling them your destination also helps when they load your luggage.