Role playing using common sentences is the best way to learn ANY language.

Start with a taxi lesson so you can move everywhere. Then a restaurant lesson so you can order from any menu at least the meals you like. Then a grocery shopping lesson. That'l cover 50% of your basic tourist needs. Then meeting people, elevator, bus, just remember the most important words 'sumimasen, onegaishimasu, kudasai, hajimemashite, arigato' and you'll be welcome everywhere you go.