I quite like writing in Word. It feels fully featured and does everything I need it to. Mike Mearls in his Happy Fun Hour writes in Word, and if it’s good enough for him it should be for all of us. However, it’s quite wonderful having your content look like a Player’s Handbook cutout.
There’s a website called the Homebrewery which lets you do that really well.
However, there’s an even nerdier way of doing it.
Today I updated my Merchants supplement to be written with LaTeX using a template from Evan Bergeron (and the other contributors) on GitHub. On a slightly less nerdy point, I’ve no idea how to write LaTeX. So, I had to turn to Overleaf which provides a simple UI for it.
It’s a good place to properly store your progress (with a perfect revision history), keep all your images and other files together, and collaborate on the files Google Drive style with other people. Nothing is locked in either – I push all my projects to GitHub just via the UI.