Some great scriptures to study on this topic are 1 Thess.4 and 1 Corin.15.

Those participating in the rapture will be those who died in Christ and then those that are alive and remain in Christ. Baptized believers in Christ Jesus who are sealed with the Holy Ghost will be "caught up" to meet Jesus in the air. We must keep in mind though that after our initial regeneration (repentance/asking God for forgiveness and turning away from sin) we must continue to strive to walk in the Spirit and not fulfill the lust of the flesh. We must put into action the Word of God and not just quote it. This includes loving our brothers and sisters and our neighbors as ourselves. We must forgive those who have done wrong to us just like we seek God's forgiveness. We are cleansed of our sins by the blood of Jesus Christ but even Christians sometimes stumble, so we have to be quick to seek God's face and ask for restoration. To walk perpetually in sin is not acceptable. I think we know when we are doing this. We know where our heart is and so does God. So when the trumpet sounds God will declare who will be raptured and who won't. We may be surprised who will be left behind, so we must not focus so much on people but on what the will of God is for our lives. As for the clothes, I belief they will be left behind. Partly because they are earthly and also because there is no purpose for them. Our bodies will be changed from mortal to immortality.