Best way to teach an new DM

[Ragnell-Master]

A friend of mine has volunteered to DM our next campaign for 5e so I can become a player. The thing is he's new to rpgs, so what's the best approach to getting him ready to run a game. He's mostly wants to do it for his untold ambitious ideas for stories, hopefully he's knows the line between player choice and railroading. Though I don't want to discourage him by getting in his way while he's trying to figure things out. How much help is too much?

[RazorChain]

I think experience is the only way to go about it. Just give him some feedback after sessions and maybe he would be better off running some one shots to start with before running a campaign.

[Knaight]

Occasional advice between sessions can be a good thing; backseat DMing will undermine them unbelievably quickly. My advice would be to cut them slack as a player, don't play hard to deal with PCs for a while, and let experience do its thing. Beyond that, being more open with your DMing techniques so they can see behind the curtain a bit is a good idea.

[Coidzor]

Pointing him at a good blog or two. Or a good podcast on the subject. There was a nice, albeit brief little attempt at a guide a while back. The Giant has some articles that might be of interest, too.

Answering questions he might have as they come up.

Maybe running a short one-shot or one-on-one session and giving more indepth feedback afterward before scaling back to talking about it from time to time after games.

[RazorChain]

Or you can just throw him into a dungeon and hope that he will master it. If he emerges, he is a Dungeon Master!

[caden_varn]

If he is completely new, I'd advise getting him to play a bit before starting DMing so he understands how it works. I'd also suggest warning him that the players will do unexpected things so the story he has in mind may have to adapt a bit.
As a new DM, he is likely to be a bit railroady I expect - it is easier to do this when you start, as winging it is difficult without a strong handle on the rules. Don't be harsh on him if so, give him some time to get his feet before expecting too much sandbox.

[LibraryOgre]

If he wants to GM, then a not-bad way is to get him started GMing. Let him start with simple scenarios... Orc'N'Pie gaming, I call it ("The orc has a pie. You want to get the pie."). Very simple stuff, that lets him get a handle on what people CAN do, and how to run the game. Done with a patient "player" interested in teaching, it's a good way to get your feet wet, and actually doesn't take too long... a couple of hours.

Also, be good about after-action reports. What's going on, what he might have done better, and stuff like that. It can also help to have someone co-GM, looking up rules and such at his request.

[Friv]

My suggestions from having been here are as follows:

1) Knaight already covered this, but I will second it: confidence is really important for a lot of new GMs, especially if they're running for people who usually run for them. Don't do much questioning during the session, don't try to be the guy who jumps in to help out all the time. Between sessions is a good time for suggestions and advice, especially if it's asked of you.

2) Maybe suggest that he use a module as a springboard? Not actually stick to it slavishly, but use the opening premise as his opening premise. (The Adventure Zone, a podcast I am quite fond of, started with the Lost Mines of Phandelvar and went in a dramatically different direction pretty early on.)

3) Encourage him to figure out his style. Some GMs do a lot of prep, and are most comfortable when they're running off it. Others really do well winging it with a lot of player input and declarations. Let him figure out what works.

4) Give feedback after the session about things that you really liked. Don't talk about things that you weren't a fan of unless they're big deals. That will help your GM friend focus on his strengths, without dwelling on his weaknesses.

[Deepbluediver]

Pre-fabbed modules are a great way to get started, or at least to build on since they lay most of the groundwork for you. I definitely wouldn't try building your own campaign entirely from scratch on the first go.

If you have the time and the patience, it's not a bad idea to let someone "Co-DM" for a session or two or for a shorter campaign to get a hand on how things look from the driver's seat without all the pressure being on their shoulders. Let the experience GM run the first session (or half a session) so they newbie can get a sense of what's going on behind the scenes, then put them in the hot-seat with the experienced GM as backup for when/if they get stuck or start to panic.

Finally, prepare for EVERYTHING and then prepare to be surprised. Even when the players aren't actually trying to derail your plot they often just get sidetracked or miss clues that should have led them down the right path. For every scenario try to think of what someone CAN do that is the opposite of what you WANT them to do, and how you're going to react to that. If you're really good, you can prep a few random-encounters (not necessarily fights) that can be applied to multiple off-the-rails scenarios. Having a high-level assassin drop into camp and start to demanding to know "what [the PCs] think they're doing" is a good way to get most people to stop and re-evaluate their current course, for self-preservation if nothing else. And it can be a good way to distribute whatever info you need to (via interrogation or notes in the assassin's pocket, etc) that the PCs might have missed. Stuff like that.