The Lord himself will come down from heaven, with a loud command, with the voice of the archangel and with the trumpet call of God, and the dead in Christ will rise first. Then we who are still alive and are left will be caught up together with them in the clouds to meet the Lord in the air. And so we will be with the Lord forever. (1 Thessalonians 4:16, 17)
If there was a trial run of Rapture, we as believers could have known how many of us are really ready for the coming of the Lord Jesus Christ in the clouds. Sadly, there is not going to be a rehearsal.
As Paul the Apostle writes to the church at Corinth, it will all happen in a flash, in the twinkling of an eye....at the last trumpet. For the trumpet will sound, the dead will be raised imperishable, and we will be changed. (1 Corinthians 15:52)
Thus, we need to be ready at all times, saying “No” to ungodliness and worldly passions, and living self-controlled, upright and godly lives. Easier said than done, some may say... But it has to be done, for being raptured to join Jesus in the clouds and life in Heaven doesn't come cheap.