There’s a lot to running a game of DnD, but unless you have a solid foundation or are a really good DM, it’s going to crash and burn. The second and most immediately important part of a good DnD game is the actual campaign. The campaign is the story – it is the lifeblood of your world, and it’s what the player characters will work through to its inevitable conclusion. Campaigns can be detailed or fairly loose, however one should always take into account who you are DMing for. It’s the players story as much as it is yours, and as a DM the golden rule is to make sure everyone at the table has fun.
While you may already have a detailed world to work in, the bones of a good campaign make the structure that will enable a fun and engaging game for your players. Your world could be the best thing since sliced bread, but without a goal your players will wander aimlessly and quickly become bored. That’s not to say you should force your players onto a specific path too much, because like too much agency, too little agency will also suck the life out of any campaign. Here the trick lies in directing your players without them feeling like you’re pushing them. Subtly manipulate them into thinking that it was their idea all along.
Making a campaign is an involved process, and can take a lot of time. However the steps are fairly straightforward as can be seen in this article describing the process in detail. This is almost exactly how I intend to go about creating and polishing the eventual campaign, however this summary has not accounted for the extra rules I will need to make to accommodate some aspects of the world unique to this setting. These rules, once made will be run past third parties to ensure their rigidity, and play testing will follow.
After all these steps are completed, this campaign should be ready to run for real.