For those of you who have been GMing for a while, what are some things you wish someone had told you when you were just starting out?

It can be about session prep, improvisation, dealing with players, managing expectations, building encounters, handling mistakes, or just learning not to overprepare everything.

What advice would you give to a new GM today, especially something you had to learn the hard way?

Make sure the game you wanna run is compatible with the type of game your players want to play.

Rifts is really fun to read, don't try to play it. There's a reason why all of the source books are on the gaming store's used book shelf.

Stop trying to be subtle with your story beats and characters. Go big, be clear, and go obvious. You're not doing Game of Thrones. You're doing WWE.

That doesn't mean you should eliminate subtlety entirely. Use it for details, mysteries, atmosphere, and character nuance. But when something is important to the story, don't make your players work to notice it. At the table, clarity is better than cleverness.

I honestly wish more people had drilled into me the value of giving meaninfull choices to the Players. I struggled a lot with constantly giving players blind choices like "pick the left door or the right door" and then wondering why they didn't feel conected with their PCs decisions and the outcomes they created.

friends don't let friends DM more than five people

I don't know what you are talking about. Players are the geese we force feed our story to to create the amazing foie gras that is our story world.

Give info freely. Don't hoard clues.

You don't already know how to run this new game just because you've played/run other games in the past.

And vice versa, don't run a game if you don't like its ruleset or setting.

Also, choose your players wisely. Role-playing games are a highly social hobby, so you need people who can behave like adults at your table. You won't find solutions for this issue in a rulebook.

Modules are great. Use them.

It is okay to make the players put in effort

You’ll learn 1000x more from actually doing it your way versus collecting opinions and watching other people do it.

Short answer:

1) create situations, not stories.
2) start small and simple.
3) run a short published adventure before writing your own epic campaign
4) PCs need motivations / drives
5) Your style will grow organically, you can't force it to be something you're not

I don't know if I'll ever get the chance to run the Cyberpunk ('Red" now. '2020' then) or WFRP game I really want now. Hopefully one day.

Start simple, for fuck's sake.