Of course, one of the main resources I’d like to point you to is a podcast which will run through the Waterdeep: Dragon Heist campaign DM’ed by me. There’s nothing like hearing the module in action.
A lot of different resources went into this campaign. Of course there was the original module itself, but I read almost daily on Reddit and Discord and other places about ideas for improving Waterdeep: Dragon Heist. When I use something from outside of the module and my own imagination I will try to cite the source. But the reality is, I have been reading and thinking about Dragon Heist since the module came out in September and at this point it is hard to remember where I got some ideas from. It’s probably safe to assume that I got these ideas from a variety of places rather than assuming these are all my own. Below I list some great resources to inspire DMs.
First of all, if you are looking for a more advanced version of Waterdeep: Dragon Heist you should definitely check out the Alexandrian Remix. This is definitely not recommended for beginners or for DMs who want to run Dragon Heist in a shorter amount of time. This will add levels of complexity way beyond what the book describes. So if you are looking to make your Dragon Heist deeper, richer and more complex I recommend giving the Alexandrian Remix a look.
This campaign doesn’t necessarily follow the Alexandrian Remix. It came out after I had already ran several sessions and I had already planned out some things like making the quests to get the keys more complex rather than using the mechanism of the eyes that the Alexandrian does. But it is a good source for ideas on how to run the module.
The Waterdeep: Dragon Heist subgroup on Reddit is a great resource and they even have a fantastic roundup thread pinned to the top that gathers a lot of great resources together. From that resource, there is an excellent set of colored maps that you can use if you play in a virtual table top like roll20. You can find more elaborate maps online, but I prefer the simple ones because I can often just substitute them in for the original and not have to change the dynamic lighting. Of course, other sites on Reddit like DMAcademy, DndBehindTheScreen, and dndnext are great for general role playing advice.
Another fine resource is The DM’s Guild. Here you can find all kinds of fantastic Waterdeep material for free or a nominal price. Some of the things from my own campaign were pulled from here like at least one scene thus far from Waterdeep: City Encounters. Blue Alley is a frequently recommended module available on The DM’s Guild. It can be easily slotted in as a side quest or one of the keys (or eyes if you follow the Alexandrian Remix) can be hidden there.
The Waterdeep Interactive Map is great for finding where certain things are located and you can also use it when the players want to stroll down a street and just want to know what sights they see along the way.
Finally, check out the Waterdeep: Dragon Heist Discord. https://discord.gg/ws4kDG4 A lot of useful resources get posted there like tokens and maps and art and sounds. Plus you can jump into one of the discussions and ask questions about any topics you find confusing.