Any suggestions you can give to a new DM?
My friends and I have all been playing for at least five years (I’ve been playing for almost ten now, and DM-ing for like three or four), and I watched my older brothers play since I was a teeny thing. So, I have advantage here.
There are a lot of online resources that can help you out with the actual organization and execution of it. I’m not going to waste your time with things you can Google (unless you need me to).
It’s always easiest to start out with a campaign that’s already been planned out, like from a book or one you found online. You can piece things together and change names and add your own elements, but don’t rush in with your dream campaign on your first go. Even if you’ve had a story/world in your head for years, it’s just easier to figure out the mechanics and the storytelling method through something that you aren’t personally connected to. Otherwise, you’ll be crushed that it didn’t work out how you envisioned it. Trust me.
Keep your players on track as much as you can. They’re supposed to listen to you, and if they aren’t, you need to find a workaround to move the story along. Let them be silly, let them fuck up, but don’t let them, like… make the campaign about three friends who open a dog grooming business. At least not on your first go. You’re going to get blindsided, and you need to be prepared for that, but don’t let them dig your grave.
Other than that, it’s really just a matter of planning, confidence, being able to think on your feet, and making it fun. We all feel embarrassed doing weird character voices, but I promise they aren’t judging you. Even if they laugh at you, it’s because you’re being funny and they’re having fun, not because you look stupid.
We were all theatre kids and most of us perform and write, so I think that helps us out, personally, but even if you aren’t used to this sort of thing, try your hardest to be open and shameless.
The sort of things the average person would consider weird, and the sort of things a bunch of pals who wanted to play D&D with you will consider weird, are two separate worlds.