It's not written anywhere in the bible exactly what the seven signs of the apocalypse will be (and many think there will be ten signs rather than seven). But they go something like this:
-Wars
-Famines
-Disease Epidemics (And other heavenly signs that are not described)
-The coming of the Anti-Christ-who will be backed by the "False Prophet"; a religious leader
-Plagues
-Asteroids hitting the earth
-Water turning to blood...and so on. That's one interpretation, but I've seen and heard of many others. And those are not in chronilogical order.
Another I've heard is those who speak of there being ten signs rather than seven:
-The Knowledge Explosion (i.e. Technological advancement.) "But you, Daniel, shut up the words, and seal the book till the time of the end; many shall run to and fro, and knowledge shall increase" (Daniel 12:4)
-Plague in the Middle East. "And this shall be the plague...their flesh shall dissolve while they stand on their feet, their eyes shall dissolve in their sockets, and their tongues shall dissolve in their mouths" (Zech. 14:12-15).
-The Rebirth of Israel.
-The Jews will return home.
-Jerusalem no longer under gentile rule. "trampled by the gentiles until the times of the gentiles is fulfilled" (Luke 21:24).
-International Instant Communication. Apparently this must exist in order for all people to see God's "two witnesses" who will "prophesy one thousand two hundred and sixty days, clothed in sackcloth" (Rev. 11:3, 7-10).
-Days of Deception. "Everyone will deceive his neighbor, and will not speak the truth; they have taught their tongue to speak lies; they weary themselves to commit iniquity" (Jer. 9:5). (Many believe this has to do with the "new age" religions.)
-Famines and Pestilence. "there will be famines, pestilence, and earthquakes in various places. All these are the beginning of sorrows" (Matt. 24:7-8).
-Earthquakes. Israel's Messiah will be announced by an earthquake: "and he said, 'the Lord roars from Zion, and utters His voice from Jerusalem; and the pastures of the shepherds mourn, and the top of Carmel withers" (Amos 1:2).
-As in the days of Noah. "but as the days of Noah were, so also will the coming of the Son of Man be" (Matt. 24:36-39). In the days of Noah, humanity was destroyed by floods because of man's wickedness, but many believe that the murders, rapes, kidnappings, assaults, child abuse, parental abuse, etc., that are evident in our daily lives are direct signs that the end is at hand.
That's all I know, but as I said, they are not biblically accurate, as none of the signs of the apocalypse are outright described.
... so I moved it to the Christian forum.