We should live each day as if it were our last and as if it were the last day for the world. Today and each day should be "dress rehearsals" for the second coming of Christ.
We have reason to believe that we will be ready for Christ's second coming if today we are managing with faith and wisdom all the resources, time, charisms, talents, and opportunities the Lord has given us (see Lk 12:42). If we are spending today feeding people physically and spiritually (Lk 12:42), we are getting ready for Christ's coming. If we are no longer living for ourselves (2 Cor 5:15) but see ourselves as Christ's slaves (Lk 12:43 in the Greek), we are ready to cry out "Maranatha!" until Jesus comes again.
However, if we spend some of this day hurting others in our anger, bitterness, or unforgiveness (Lk 12:45), we are not ready for Christ's coming, or our own death, or this day. Also, if we live this day to maximize our pleasures (see Lk 12:45), we are not ready to live forever or even for today.
If we are ready for Christ's second coming, we are ready for anything, even for today. Live on the edge — the edge of this world and this life.