How to Fabricate a Claim
All titles require a claim and a Casus Belli on the title by the character. You can get both mainly by using your Court Bishop or equivalent religious member of your Council to fabricate a claim. Start by going to the Council on the right side menu or by using the Hotkey Shortcut F4. Once the Council menu pops you will go to the top right where the Court Bishop or equivalent religious title. There will be a few options for the Bishop to choose from, but the one you are looking for is the symbol showing a hand grabbing a blue shield, as seen in the image below.
Click the button as shown and you will be able to fabricate a claim on a County and the map will then show you all available domains owned by rival nations you can fabricate a claim on. The only ones available will be one’s in close proximity to your nation’s borders. All areas you cannot fabricate a claim on will be grayed out.
Left click on the County that you are fabricating to select it. This will assign your Court Bishop to start fabricating the claim on that domain. This will take several months or longer to complete the fabrication process. The length depends on how high the Court Bishop’s learning skill is. Make sure you have Court Bishop with a high learning skill to ensure quick fabrications, which you can see in the upper right next to the book symbol above the Bishop.
Once the fabrication claim is completed by your Bishop, you will get an unpressed claim on the Domain/Title you selected if you decided to pay for the paperwork to be completed. If you don’t you will lose all progress the Bishop has made and will have to fabricate the claim again once you have the gold. After you have the unpressed claim you will be allowed to declare war with the Casus Belli to claim that domain/title. Now just win that war and gain control over the domain and that Title.