Do several things:
- Equip a few colonists with guns to be soldiers, perhaps one or two per city. This will dissuade the natives from attacking you, and hopefully allow your cities to survive if and when they do get fed up and attack.
- Equip a few colonists with guns and horses to become dragoons. This will allow you to react more effectively if and when the natives decide to declare war.
- Buy a couple of veteran soldiers from Europe, and always choose them when they are ready to appear on your dock. You won't get very many this way, but a couple of them can really help.
- Stockpile as many guns and horses as you can, both in your colonies' warehouses, and in extra wagons.
- As soon as you declare independence, transform as many colonists as you can spare into soldiers and dragoons. Fortify the soliders, especially in your coastal cities and in hills or woods (or better yet, wooded hills) adjacent to your coastal cities. Be ready to send groups of 4 to 5 or more dragoons to attack any of the King's armies that land.
That's pretty much it. Produce as many guns and horses as you can!
Cheers, --- Wheldrake