Recently a new member of the FreeCol forum on SourceForge said he was getting slaughtered and asked if anyone could advise. The following was one reply:
"Normal" mode may be a bit hard for someone who's not very familiar with the tricks.
In the game I'm on, in "easy" mode" as Swedish with the building advantage and on the smallest standard map but with maximum landmass, I was very lucky to get offered De Soto first. Having noticed that the Euros don't know how to spend gold, I had given everyone $9000 at the start, so by 1495 I had one colony from my original contingent and another from the privateer, with a galleon on its way to carry scouts and wait for treasures. In 1496 one good sale was 100 trade goods $868. 1497 sold 100 trade goods $892 (but higher prices came later with smaller amounts offered) and bought second privateer (useful for sending scouts to far-flung areas no other power had even heard of).
I was concentrating on liberty bells. De Soto joined the Congress in 1499, at which time five of my rivals still had $9000. My scouts (every man who could lay hands on horses) swept the mainland and outlying islands cleaning up Lost Cities. First treasure train was found in 1500 and was safely on the High Seas by 1503. I got one Fountain and about nine visits to El Dorado. By 1511, the year I found El Dorado four times, I had nine colonies and 48 units, and the other seven powers had between them just 12 colonies and 55 units. Much of my gold was gifts from natives whom my scouts visited when they had time; the first few such visits from 1495 to 1505 yielded 376, 348, 189, 222, 109, 1081, 643, 660, 1280, 992.
By 1520 I could see that some other powers were importing large numbers of military, but all of my colonies were ready, several with artillery and the rest with dragoons or at least soldiers.
Strangely, though, it's now 1547 and nobody has attacked me. Maybe they realise it would be painful. I have 29 colonies and 137 units, the others a total of 25 and 140; my military strength is 116, with next being Spanish on 42 and English on 39. My naval strength is 90 (2 frigates and several privateers), contrasting markedly with the 16, 14, 8, 0, 0, 0, 0 of the rivals.
If my privateers had been "naughty" attacking peaceful ships I might have been even better off, but that's against my principles. Still, if anyone pushes me off a tile I'm producing from, he may find some black ships causing him a bit of trouble.
So - start everyone off with at least 9000 gold because you can spend it more intelligently, and go for explorers so that you can get De Soto as soon as possible (visiting natives before he arrives) then put lots of people on horseback to get a really good head start. Use ships to sell trade goods (and pick up a few bargains in raw materials).
When the attacks come, hit the enemy artillery while they are vulnerable out in the open.