First and foremost this is a BEGINNERS GUIDE, I don't claim to be good at the game or know much about it, I'm basically a beginner myself, and so knowing how hard it can be to find your feet as a beginner I thought I would try to help those fairly new to the game.

I play vanilla, no expansions.

OK so this guide is for those who already have a grasp of the game and have played around as an independent ruler and want to try the game playing under a liege.

This is written assuming you are a count under a duke, under a king/Emperor.

First off your main goal is to acquire a duchy just like you would as an independent, the problem being you can't create or usurp one if you have a duke liege. So your first target is to gain enough power to get Independence from your liege. You can do this by fabricating claims on counts that are WITHIN your emperors land IF the crown authority of the highest liege is below medium. If it is above this then you will have to target land outside your emperors rule. DO NOT TRY TO FABRICATE LAND OF YOUR IMMEDIATE DUKE LIEGE, also DO NOT MARRY INTO YOUR IMMEDIATE LIEGES FAMILY, this will create a defensive pact that will stop you from demanding your independence from them.

So to summarise if your top lieges crown authority is below medium then fabricate claims on a duke INSIDE your emperors land THAT ISNT your direct liege. You basically want 51%+ of a single dukes land so you can plot to take his ducal title. A reminder, you CANNOT create or usurp a duchy if your direct liege is a duke.

So once you have acquired enough power, usually around 4 counties + enough money to buy mercs if you need them (1000 gold) then you can demand independence and then fight your duke for it. A quick tip is to have your troops bordering their land just before you do this so when you start the war your troops will effectively ambush theirs and yours will have full morale, if you time it right then they won't even raise theirs if your troops are already en route.

Once you have won your right to independence then congratulations you can now create a duchy! If you check you plot screen then you should have options to fabricate claims on any duchies that you have 51% control over APART FROM your original lieges duchy. I honestly can't remember the reason behind this, I'm sure you can find the answer to this elsewhere on the net.

This is the best and easiest way to start as a count under a duke as a beginner, I'm sure their are other ways that may be either better or more fun but again this is a BEGINNERS GUIDE. A quick tip is to fast forward until you have about 1000 gold, doing just the basics (getting 2-4 fabricated claims lined up, getting your dynasty set up with marriages and heirs and changing your succession to ultimogeniture or primogeniture) and then use just mercs to conquer the counties one by one without disbanding them in between, using the aforementioned ambush tactic works perfectly when using mercs.

You can try to obtain a duchy through marriage but this is insanely complex and time consuming and in my opinion not very fun, although it is satisfying if you manage it. I did this on my first attempt as playing as a count under a liege and it took all day and about 150 game years and 3 generations of my dynasty and far too much brain power haha! If you want to know how to do this then let me know and I will post a how to guide for that route, but the fighting route is much more enjoyable.

A few more advanced techniques to try once you have acquired a duchy are below

supporting factions weakens top liege.

Be leader of factions that either- grant independence, change crown laws.

Killing liege and sow dissent in leiges capital

Killing lieges wife to make plots easier

Kill councillors that u want to be assigned to

Kill marshals to weaken leaders

Kill lieges vassals that like him

Assassinating heirs of vassals and lieges to get your sisters on thrones matriliniary

Educate lieges children to change their culture so when they come in to power everybody hates them and revolts happen more frequently. This only works if your culture is different to your liege.

I hope this has helped and thanks for reading!