Making Money will unfortunately be a problem that will plague you throughout the game; War is something that as a ruler you will have to come to terms with; and you don't necessarily have to field your Armies in the name of the King (However this is damaging to both your reputation and your loyalty) The best way to make money is taxes, build building that make your Burghers, Peasants, Nobles, and Clergy more loyal so you can turn around and tax the hell out of them, when their loyalty gets below 50% lower your taxes to 0-10% and see their loyalty come back up. This is especially handy in lean times (you know the phrase Lean times means lean measures). Also it depends on who you're giving power to, naturally in your cash-cow provinces (Income is 4 or higher) Give Burghers the Power, less than 4 give peasants power, in Non-Native Cultural lands give Nobles Power, and in regions with a different religion than your own give Clergy an extra oomph. Also, your major money making schemes will involve inheritance, Wed your eldest sons or daughters to wealthier family (De Normande, Capet, Flanders (I think), De Hauteville, Hapsburg (in later games), Platagenet, etc. etc.
And as an easy starter faction, avoid Kingdoms until you know how Loyalty Works, and go for an easy Duchy, The Belgian Duchy (forget the name) is a good starting point, Big Armies, Very Good Income, and Fiercely protected by the French Aristocracy. In the first 100 years of the game, getting a lot of money is very difficult, it will require penny pinching galore, and don't be surprised if you find yourself well over a thousand Gold in Debt. But as technology and Population increases your means of money will become less stressful. The point of the game isn't to conquer the world, and war isn't very profitable anyways, you need to marry off the right heirs to the right people, and hope they produce liable off spring.
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