What advice would you give to a foreigner coming to Korea for the first time?

In South  Korea always greet formally becaese country of courteous people in the East.
In other countries not address high language title honorific pay careful attention and in
Korea first meeting is important becsuse the first meeting is important because the first image for older adults who met for the first time or whether a smile and a good idea to politely greet.
Also when come to Korea eat food adults should eat first and eat up all '잘먹겠습니다' (I'm finished) good idea to say food thank.
When drinking at a party with adults in the head by turning the drink.
These kind of things basic manners comes to know adaptation will faster in South Korea :-)