Suggest me some settings and self-imposed rules to improve my Warmongering

[CornPlanter]

3) India (acceptable alternatives are Portugal and Dutch). In other words, learn how to coordinate the regular units first, then worry about learning the exceptions

One of the most usefull advices I've ever heard on this forum (No sarcasm here)

 

[Shurdus]

Think about the decisions you are making. Your decisions should be geared toward war. That doesn't mean you can't make friends (that you backstab later) or that you can't focus on economy at times (in order to get advanced military tech, or avoid falling behind in tech). It just means that you are always thinking: "Who is the next target? What is the best way to take them out?"

If you are going to build a wonder: "How does this help me take out my next opponent?"

If you are going to build a building: "How does this help me take out my next opponent?"

If you are going to select a tech to research: "How does this help me take out my next opponent?"

If you are thinking about diplo relations: "How does this help me take out my next opponent?"

If you are looking at the power graph: "How does this help me take out my next opponent?"

If you are building more workers: "How does this help me take out my next opponent?"

If you are cranking out an army: "How does this help me take out my next opponent?"

If you are contemplating switching civics: "How does this help me take out my next opponent?"

etc.

What about improvements?

Seriously, get yourself into a war and see how stupid the AI manages his armies. If you do not get confidence in your own abilities then I do not know what will. Also you will want to learn how many units you should bring. Bring too many and you will hurt your economy withoutn justification for that, bring too few and you will not take and hold cities. This takes experience and should be learned on a trial and error basis.