You'll have to add three main zones in your city if you want it to grow. While you want to keep them separated, don't move them so far apart where the residents will have to drive too far. Though let’s say you put the residential zone next to the industrial zone, if you do so, then pollution and crime rates will rise in that area, and the residents will quickly want to move.
- Residential Zone
- This is where the residents all live. Keep them a good distance away from industrial zones, though not to the point where it's to far away. If residents don't want to move where you want them to, then maybe add some schools and attractions, because they love that stuff.
- Commercial Zone
- This is where the sims go shopping, and thus you'll get a lot of tax money if you have plenty of commercial zones and residential zones.
- Industrial Zone
- This is where the sims will work. However, it causes a lot of pollution, crime, and fire rates, so don't add too many of them.