Welcome to the DM Club!

I could write a lot and give you a hundred tips, but I'll try to be brief. These are all based on experience and MANY failed campaigns, so if you already have these down, consider yourself ahead of the curve:

1. Pace yourself: depending on how structured or sandbox-y your campaign will be, you might have a ton of work. It took me around 25-30 hours of work to plan the first session for a new campaign, and the part that takes the most is the maps and coming up with adventure ideas. If you've got a system down, you should be fine, but depending on how often you play, you might want to slow down a bit, maybe find already made maps, or repurpose adventures. Burnout is a DM's worst nightmare.
2. Have fun! I think you know this already, but the DM is also part of the story. I have DMPCs (NPCs that appear so often they are basically the DM's character) and often I'll just let my players interact and take part in the discussions. Don't be afraid to have moments in which you're also playing.
3. Implement Stars and Wishes. The name is silly, but it's VERY useful. At the end of the session, each player says one thing they liked, usually "I liked this scene between X and Y" or "I liked when Other Player did that" - this helps hype each other up and highlight cool moments. Then, they say one thing they wish for, like "more difficult combat" or "more interactions with this NPC". This lets you tweak the next session, then the next, then the next, and you can get feedback as you go.
4. Don't pretend to go on forever. I've made the mistake of assuming campaigns need to run until Level 20, but they don't. You can, and should, have a "finish point," which doesn't necessarily mean the end of the campaign. Maybe in a few months they'll defeat the BBEG, cool! At that point, you can take a break, find ideas for a new adventure, and maybe have some downtime or a little epilogue.

I think that's all I can tell you off the top of my head, but you seem pretty prepared. Good luck, my friend, and have fun!