Here's a quick and dirty one:
1. Get up to 6-8 bases, maybe HGP if you have time/want to increase the number of cities you have.
2. Terraform moderately by giving Forests on any non-rolling tile and plant roads connecting the cities.
3. Give every city a Recycling Bin or Rec Common. (Rec Commons aren't really needed, but it's up to you) Every city should have a decent mineral output by now.
4. Hoard up, and smash your neighbours.