Seriously now...
They do rehearsals in two times, the first one they gather in a rehearsing room and they start playing the songs one by one until they learn them. That could last around two weeks.
Then the last week they move to a bigger venue where they play what is called production rehearsals. They play all the songs at a big stage while technics try the PA sound, the lights etc. When they end this process, they do a full show usually without any public to check everything is well.
Then they took some free days until the first concert.