Apparently I'm going to be DMing a 4.0 campaignFollow

I have 3 friends who have never played D&D before, and really want to give it a shot. I've never DM'd before but I'm the best candidate since none of them have played at all. I have their character sheets and backstories, now I just need to actually... create a campaign >_<. Any tips? Was thinking about trying a premade one, but they all worked hard on their backstories so I want to be able to incorporate their ideas as much as possible.

It doesn't appeal to me, but it's fairly easy to understand, in my opinion.

Fully custom campaigns are huge amounts of work. The good news is that you can use a premade and choose the amount of customization and effort you want to put into tailoring it to them. One solution might be to use a premade campaign as a base, and introduce some characters and elements of their backstory into the setting. Does a guy have a nemesis? His nemesis now lives in your world. Is a guy from a certain tribe? His tribe is now a part of your world.

Have an idea of how long the adventure is going to be. An adventure that goes from 1-8 is going to have very different character development pacing than one going from 1-16. For example, if one player has a nemesis that you want him to meet, that nemesis might be the main villain (or sub boss) of a single arc in a 1-8 campaign. However, in a 1-16 campaign, maybe the nemesis is a bit higher in the hierarchy and so the party fights some of his lackeys first to introduce him more gradually.

Try to take things from characters' backstories and give them a moment to shine. Does one character know several languages (at the cost of more functional feats) as part of his backstory? Then perhaps some part of the adventure will require a translator. IS one guy really good at sewing for god knows why? Then perhaps the party's sail is ripped to shreds at sea and must be repaired before they can progress.

As a player, it not fun if I worked on a backstory that has no relevance to the game. Find something that they wrote and make it a part of your world, even if you're still mostly doing a premade campaign.

Or, listen to one of the guys here who gives good advice.

My main issue is I don't want it to seem contrived. Also the 3 players have fairly different backstories but with the same theme (a friend / loved one was kidnapped / murdered by bandits / orcs and they want revenge. But little does the character know that the person isn't actually dead, but rather part of a much larger plot!). It's so cliche it hurts, and with all of them being so similar but with different actors for each I'm having trouble figuring out how to intertwine everything.

It could be worse. You could be trying to find a way to fit a world to one of my backstories.

But yeah, do what Spoonless said.

I found a couple potential adventures that would be a good start. I'm assuming that this campaign will stretch over multiple adventures. How much should I change the first one to include elements of their backstories? At all, or can I save that for future adventures? Also, is it better to run a single adventure completely in a session, or can it be broken up into 2 sessions?

True... I just feel that I'm not going to do a good job and they're going to hate me forever, or something. :(

This is how i feel anytime i do, or think about doing anything

If only that was enough to make me stop.

you're dumb

Those two things aren't exclusive...

"The reason why rocks are falling in a tavern is Rachel9 is hit by a meteor and is vaporized. The rest of you roll CON to avoid instant death."

"Oh, you succeeded on your CON rolls? You avoid instant death, but you die from...mythicalichate...exposure from the meteor within seconds. It's very tragic. Poems are read aloud in your memory in Town Square yearly, blah blah blah, someone else's turn to DM."