How do you reduce lag?

Since there are so many terrains and models in my project and scene, it lags a lot, but how do i reduce it?

  1. Set all stationary models as static.
  2. Reduce the texture size.
  3. Run the profiler to see if its your models, or your scripts.
  4. See #3.
  5. Turn off Camera Filters (Anti Aliasing, SSAO, Tonemapping, etc. if you have any added)