If you have tactics that work well (like ones the computer uses) post them here.

1. Always build roads leading to a city before you build it.
2. Always build irrigation around the future site of a city before you build [the city].
3. Only use Democracy or Fundementalist governments (sometimes republic and less often monarchy)
4. Make as many alliances as possible. (it gets you military, economic, and scientific help).
5. Use spies and diplomats to incite revolts, steal technology, and sabotage stuff.
6. Don't build small, loose cities. Build connected (roads), tight, large cities. When you get mobile warfare, robotics, and the space race [started], larger cities will build things much faster for you.

Well i'vedone a amazing thing!!!.I waged and won a "world war"on two fronts.I had nukes so I bet them with mega force so they were.

i only use democracy
i always keep my towns 5 spaces apart. TooooT
i always build irrigation last
i always make sure i get democracy, riflemen, explosives, farmland right away.
i always cheat too

Putting a spy in each of my cities, they stop and enemy attack and prevent other spies spying.

Put cities in best suited locations if you read how topography works.

Trade technology with one of the other two civs then take them over or have them declare war.

Blow up the capital of my enemy only so they can't switch government.

I'm scientific in this game.